Best Gravity Water Filters 2026: Lab Analysis & Hands-On Testing

Gravity Water Filters

• Custom Gravity Water Filter Combo
• Patriot Pure Ultimate Water Filtration System
• Phoenix 2.25-Gallon Gravity Water Filter

Please note: This page is still a work in progress. Additional content and details will be added shortly – stay tuned!

Paraphrased Video Script

British Berkefeld, Patriot Pure, Berkey, Culligan, Phoenix, Alexapure Pro, and more – we just finished our second round of gravity water filter testing, with 18 different setups reviewed in total.

And honestly, I don’t think we’ve ever seen this many cases of potential contaminant leaching above health guidelines in one comparison.

The good news is, once we dug through all of it, we did find a few hidden gems that are absolutely worth looking at. We also built our own custom combo using what we think is the best system housing with the most effective filter element – creating the ultimate gravity water filter – and we’re really excited to show you that.

So yeah, we’ve got a lot to cover, so let’s get into it.

 

Now, our first gravity filter comparison back in 2024 included no more than 7 systems, and some people felt we focused too much on the Big Berkey, which was our top pick at the time.

But we said we can do better, and so we’ll keep it tighter and more balanced across our top picks in this video. And we’ll also make sure the other systems get proper coverage too.

And so today, this is Gravity Water Filter Comparison 2.0 — with a bunch of new configurations lab-tested and hands-on tested, a few older ones re-tested but with a different lab and water supply than in 2024, and a custom combo we came up with that should be really hard to beat.

Also, this is going to be a mini-series. In this first part, we’re focusing on day-to-day usability and our lab results using tap water. We’ll still give you our top outdoor pick, but in part 2 we’ll go much deeper into treating water in an SHTF scenario. We’ll also test the most promising filters on a local surface water source — probably a pond — to see how they handle real-world germ reduction. So if you don’t want to miss that, make sure you’re subscribed and hit the bell.

 

Alright, let’s quickly introduce the gravity filter configurations in this comparison.

First up, the British Berkefeld SS2. In 2024, we tested it with the Ultra Sterasyl filters and got pretty disappointing lab results. This time, we switched to the Ultra Fluoride filters, hoping for better overall contaminant reduction.

Next, the Alexapure Pro. 2024 lab results were solid, so we tested the exact configuration again.

Re-testing the same Big Berkey setup as in 2024 didn’t really make sense. Black Berkey filters are still widely unavailable due to an EPA stop-sale order, so this time we used Phoenix Gravity New Millennium Edition filters — which are officially endorsed as a replacement.

Speaking of Phoenix, we hadn’t tested the Phoenix Gravity Water Filter system yet. At first, we tested it with both carbon and fluoride add-on filters. Results looked great, except we saw signs of leaching of some form of aluminum way above what we’re comfortable with. We suspected the fluoride filters, so we ran another test without them.

Same story with the Purewell 2.25G, which is currently one of the most popular options on Amazon. In 2024, we tested it with both carbon and fluoride filters, and the lab reported elevated aluminum levels. So this time, we skipped the fluoride filters entirely.

3 more systems we hadn’t tested before are the Patriot Pure Ultimate Water Filtration System, the Radiant Life SS Gravity Countertop Filter, and the Rorra. All 3 were tested with their official filter elements.

Also new is the BOROUX Legacy. We tested it with 2BOROUX Foundation filters and 2 optional Proactive Fluoride filters.

Another new one is the Culligan Scout, which wasn’t available during our first comparison. Culligan basically took over ProOne in (we believe) 2024, and ProOne systems are now being phased out. So instead of re-testing our 2024 ProOne Traveler+ unit, we tested the Culligan Scout using their MaxClear filters.

And that leaves 2 systems:

The Waterdrop King, which we tested in 2024 using both Black and Fluoride filters, but with very poor lab results, and since nothing has changed, re-testing didn’t make sense.

And same for the Santevia Gravity Water System –2024 lab results were too weak to justify another round.

Okay, that’s 17 systems total. And as you probably noticed, most of them have a very similar build. The main exceptions are the Rorra and Santevia — and to some extent the BOROUX, because it’s a larger 3-gallon system instead of the standard 2.25 gallons.

Now, because of that similar build, most of the filter elements are interchangeable. So we took the best-performing filter from our lab tests and paired it with the best housing. That gave us our own custom build: system number 18.

We’re going to reveal that next, along with its pros and cons. We’ll also cover 3 more top picks, and then wrap up with a quick-fire round of the remaining systems explaining why they didn’t make the cut.

 

Alright, our top gravity water filter recommendation — system #18 — uses the Phoenix Gravity Water Filter housing paired with one or more Patriot Pure Nanomesh filters. Combined, this setup achieved the highest overall rating in our comparison.

In short, we think the Patriot Pure Nanomesh filter offers the most effective filtration. It didn’t just score highest in our lab testing with almost all contaminants removed to 100%, it also has by far the most contaminants actually certified for reduction against NSF standards. The other gravity filter elements aren’t even close here, so that’s a big differentiator.

That said, the housing of the Patriot Pure Ultimate Water Filtration System didn’t fully convince us. And we think the Phoenix housing is the better choice. It scored highest in our usability testing, it’s very affordable, and it comes with a long 10-year warranty.

But there’s more to it, so let’s go step by step and explain why — even though it’s not perfect — this custom combo is the best option and, in our opinion, worth spending a little extra on.

Starting with our lab testing:

We assembled and primed each gravity filter setup exactly according to the manufacturers’ instructions, then ran a simple before-and-after comparison using our tap water. We filled a large bucket, poured equal amounts into each unit, took one unfiltered sample directly from the bucket, and one filtered sample from each system. All samples were analyzed by an independent lab.

Quick disclaimer: this kind of testing isn’t an exact science. Things like handling errors, cross-contamination, or natural variations in the water can affect results. We can also only test for contaminants that are actually present in our water supply. And for each round, we typically test one unit per model. So think of these results as a snapshot, not a final verdict.

With that in mind, let’s look at our lab results as a whole to get the bigger picture.

These are the 2026 results. We tested 11 different setups, plus our custom combo, so 12 in total. Each row represents a contaminant. Everything above the bold line was present in our tap water before filtration, and everything below showed up only after filtering — meaning potential leaching.

Color-wise, dark green means full removal, light green is still strong, white is neutral, yellow means the concentration at least doubled— not ideal, but not necessarily a problem depending on the substance – and orange means the increase exceeded the strictest health guideline we could find — so orange is always bad.

And so looking at the 2026 results, there’s a lot of green, which is good. But there’s also quite a bit of yellow, and 5 cases of orange — especially toward the right side of the chart. That’s because we arranged the systems from best to worst based on their final ratings.

If we compare that to 2024, lots of yellow as well, and again 5 cases of potential leaching above health guidelines — which is kind of crazy when you think about it. These filters are supposed to make your water cleaner, not dirtier.

Now, none of this is set in stone, and again, this type of testing isn’t perfect. In theory, the leaching could be caused by something else. That’s why we call it “potential” leaching — we don’t want to overstate anything. But for cases like aluminum, where levels were quite high, we have a pretty good idea what might be going on: the optional fluoride filters potentially releasing some of their activated alumina media into the water — something we already discussed in our first gravity filter video.

Also worth noting: substances like chloromethane, benzene, toluene, methylene chloride, vanadium — we’ve found those multiple times in filtered samples, but never in our unfiltered tap water.

So overall, we’ve never seen more cases of potential contaminant leaching above health guidelines than with gravity filters. For comparison, if you look at our latest countertop reverse osmosis results, there’s just a single orange cell and very little yellow.

Anyway, let’s focus on the Patriot Pure Nanomesh filter, which performed best in our testing.

What’s important is that we tested it in the original Patriot Pure housing. But during our usability testing, we actually preferred the Phoenix housing. Plus, there are additional reasons for that preference which we’ll cover in a moment. So we checked if the Nanomesh filters would also fit the Phoenix system, and they fit perfectly fine, with no leaking whatsoever – not too surprising, since both systems are almost identical in size and design. We also saw very similar filtration speed when using the Nanomesh filter in either system.

So based on that, we don’t think it really matters which housing you use. At the end of the day, it’s mostly just a different name and logo on the tanks. Filtration performance should be the same, and so our lab results should translate, which is why the custom combo uses the same data as the Patriot Pure system in the chart.

Now, looking at performance: The Patriot Pure Nanomesh filter removed chlorine, all 3 detected disinfection byproducts, copper, iron, manganese, nitrate, and fluoride by 100%.Barium was reduced by a near-perfect 98%, and boron by 94% — both very strong results. The only real issue is strontium, which increased by 91%, from 0.132 to 0.252 parts per million. That’s likely too large to be just natural variation, so not ideal. That said, the strictest public health guideline we could find for strontium is 1.5 ppm — about 6 times higher than what we measured. So from that perspective, we don’t consider it a health concern at all. Still, not ideal. Other than that, there were no signs of potential leaching. So overall, really strong lab results.

And as always, our full comparison sheet — including all lab reports — is linked in the video description. Or you can just go to bos-water.com. It includes our full analysis of every system, plus product links. If you use those, you’re supporting the channel and helping us run even bigger tests going forward. As for discount codes — we did try to get one for each of our top picks, but either didn’t hear back or got turned down. So unfortunately, no luck there, but maybe that’ll change after this video goes live.

Okay, our lab data isn’t the only thing that goes into the filtration score.

Another factor is filtered water aesthetics. And with the Patriot Pure Nanomesh filter, taste was perfectly clean and all odor was gone. Although to be fair, that was the case for all tested gravity filters.

The final — and in our opinion very important — piece is NSF standards for contaminant reduction. And this is another area where the Nanomesh filter clearly stands out. It’s certified against NSF standards 42, 53, and 401 for a total of 75 different substances, including chlorine, arsenic 5, chromium, lead, PFOA and PFOS, VOCs, and a range of so-called emerging compounds like pharmaceuticals, pesticides, and industrial chemicals.

If you compare that to the other filters, most of them aren’t certified at all. Some are certified for chlorine only. The Culligan Scout is a bit better with about a dozen certified contaminants, but still nowhere near the Nanomesh filter. And that’s a key point, because NSF certification requires very strict testing across the entire filter life — not just at the beginning.

Now, technically, those certifications apply to the Nanomesh filter when used in the Patriot Pure System — not the Phoenix system. But as we explained earlier, the two housings are basically identical, so what really matters is the filter element itself.

On top of that, Patriot Pure also provides additional third-party test data — which we can’t show here for copyright reasons. But you’ll find it linked in our comparison sheet. That data shows testing for contaminant reduction from 100 up to 400% of the rated filter life, which is great. And we counted more than 195 different substances — possibly with some overlap — including a wide range of VOCs and semi-volatiles, PFAS, pesticides, trace pharmaceuticals, industrial chemicals, and heavy metals.

Some other systems have a similar number of substances tested, sometimes even more. But in many cases, it’s unclear whether that testing was done across the full filter life — and we’d say probably not.

So bottom line: the Patriot Pure Nanomesh filter delivered the best lab results, clean taste, and by far the strongest NSF coverage. That gives it a filtration score of 4.26 out of 5.00 — which applies both to our custom system #18 and the Patriot Pure Ultimate Water Filtration System.

One more important note: right now, the Nanomesh filter is not our top recommendation for non-potable water. Even though the website says it can trap bacteria, viruses, and cysts, we couldn’t find any test data specifically on germ reduction. So we’ll recommend something else for that later.

Alright, next up is usability — starting with initial assembly and filter priming.

Overall, all of the systems are easy to set up, and the process is pretty similar across the board. The only 2 exceptions are the Santevia, which is more involved — for example, you need to boil the mineral stones — and the Rorra, which works a bit differently as well.

To show you how setup typically works, we’ll use the Phoenix system with a Nanomesh filter as our example.

First thing we noticed: the Phoenix system was packaged really nicely. The instructions were clear and included helpful illustrations. In contrast, the Patriot Pure instructions had a lot of text and only 2 illustrations, so not as user-friendly. But honestly, that’s a minor issue, because the process itself is very straightforward. Plus, there are tutorial videos for both systems on YouTube. The Nanomesh filter comes with its own instructions, which are solid.

You start by washing the lid and both tanks, then attach the knob to the lid and install the spigot. Normally, you’d prime the filters by holding them against your faucet using a washer or silicone sleeve. But the Nanomesh filter doesn’t require priming, so you can install it right away. Just add a washer to the threaded stem, insert it through the upper chamber, screw the filter onto it, and repeat if you’re using multiple filters. Block any unused holes, place the upper tank on the lower one, and fill it with water. Some manufacturers recommend discarding the first 1 or 2 batches, which also applies here. After that, give the lower tank a quick rinse — and you’re good to go.

How about daily use?

Again, since most gravity filter systems are very similar, they also behave very similarly — with just a couple of differences. The main one is filtration speed, and the second — smaller one — is dispensing speed. Beyond that, most differences are pretty minor.

So let’s start with filtration speed.

It’s fastest at the beginning of the process, since more water in the upper tank creates more pressure. So for consistency, we filled each system to about 1” below the rim, then measured how long it took to reach dispensing level.

Because of spigot height, most systems need at least 32 ounces in the lower tank before you can actually start dispensing — with the Rorra as the exception at just 2 ounces. The highest we saw was 50 ounces for the British Berkefeld.

The Phoenix and Patriot Pure systems came in at 34 and 49 ounces, which took about 1 hour 27 minutes and 1 hour 41 minutes, respectively. That said, this isn’t a big issue in practice. During normal use, your lower tank will already be filled to that level or higher, since you’re not usually trying to drain every last drop. So that minimum amount just stays in the system until you decide to fully empty and refresh it. From there, it took 7 minutes 45 seconds for our custom combo to filter and dispense 1 cup, and about 1 hour 8 minutes to dispense 4 cups. Processing the entire feed tank took just under 7 hours and yielded about 1.74 gallons of filtered water, with a clean reservoir capacity of 2.08 gallons. The Patriot Pure system was very similar, as expected.

But at around 8 to 10 minutes per cup and over an hour for 4 cups, filtration is on the slower side — and it only slows down further as the water level drops.

To improve speed, you can run 2 or more Nanomesh filters in parallel. The 2.25-gallon Phoenix system supports up to 4 filters — same for the Patriot Pure and most other systems.

And that’s how we handled scoring. We treated each combo as if it was being used with 2 filters in parallel, to keep things consistent— with a few exceptions. The Santevia and Rorra don’t support parallel filtration. And for the British Berkefeld with Ultra Sterasyl filters, the package already included 4 filters, so we used all of them — and it was still relatively slow.

Also worth noting: adding more filters shouldn’t affect filtration performance, since contact time with the media stays the same — it just reduces available space in the upper tank.

With 2 filters, we estimate our custom combo would take about 3 minutes 53 seconds for the first cup, 34 minutes 12 seconds for 4 cups, and around 3 hours 30 minutes for the full tank. The Patriot Pure system is slightly slower but close. And compared to all setups in this comparison, the Nanomesh filter falls below average in terms of speed. It’s still fast enough for daily use, but certainly not ideal if you want filtered water on demand.

Now, before we move on, there’s one important detail we need to mention to avoid confusion: as we were wrapping up our gravity filter testing, we found that, while the Nanomesh filter itself stayed the same, the Patriot Pure system housing had been updated. In other words, this is the old Patriot Pure housing, and it’s no longer for sale. But we didn’t want to delay the video, so we decided not to order the updated version and repeat all our testing. Based on the product description, though, the new housing is only 14” high versus 19.2” for the old one. And looking at the product photos — which we don’t have permission to show — the feed tank appears to be shorter than it used to be.

That should mean even slower filtration speed per filter element, because you’ve got less water and so lower gravity force. Now the redesign does fit up to 5 Nanomesh filters, but using that many filters means even less room for water.

So long story short, all our usability results apply to the old Patriot Pure system. And without having done any hands-on testing of the redesign, we’re not convinced by it, because it may slow filtration even further, which is another point in favor of our custom combo – hopefully that makes sense.

Okay, and that wraps up filtration speed. So let’s quickly move on to dispensing speed, which we tested using a full lower reservoir.

That matters because, just like filtration, dispensing speed decreases as the clean tank empties — just not as drastically. Across all systems, it took 3.5 seconds on average to dispense the first cup from a full tank. Our custom combo — so the Phoenix system — was almost twice as fast, dispensing the first cup in about 2 seconds. That was the fastest we measured, and it actually feels quick enough for daily use. The Patriot Pure system, on the other hand, needed 5.25 seconds. Still fast, but noticeably slower.

Now, you might not think dispensing speed matters much, but in our opinion, it does. You’re using this multiple times a day, so if it’s slow, it adds up. And it gets worse as the tank empties. We tested this and found that dispensing time roughly doubles between a full and a low tank. So if a system already takes 5.25 seconds per cup when full, you’re looking at around 10+ seconds when it’s low. In fact, we measured about 12.75 seconds for the Patriot Pure — and that definitely feels slow. So that’s another point in favor of the Phoenix system.

A few more quick notes on dispensing:

• There was no splashing with either system during normal use.
• Also, with all systems except Rorra and Santevia, you can’t fit a glass underneath the spout unless you move the unit to the edge of the counter or use a tank stand. The good news is, all systems either include a stand or offer one separately. And you can also use a generic stand. In fact, the stands we’re showing here are from Purewell and Culligan, which work perfectly fine.
• That said, even with a stand, you still won’t be able to fill a large bottle or pitcher unless you move the system to the edge.
• One small plus: both the Phoenix and Patriot Pure stands have rubber feet, which help prevent slipping and scratching.
• One downside on the Patriot Pure system is the spigot cover. It’s well-intended, but it gets in the way and becomes annoying pretty quickly.
• Also worth noting: the Patriot Pure uses a plastic spigot, while the Phoenix uses 304 stainless steel.

Last part of everyday use is refilling.

It’s simple — you just pour water into the upper tank, for example using a pitcher. Most systems don’t give you a max fill line or tell you exactly how much to add. But that might be intentional, because the right fill level depends on how much water is still sitting in the lower tank. If you just top it off while there’s still water left, you’ll likely end up with overflow.

That actually happened to us. And we tested it with some of the most flow-restricting filters to see if that would make a difference. It did reduce how much leaked, but it still overflowed.

So you need to be a bit careful here. Don’t overfill — but also don’t wait until you’re basically out of water, because then you’re stuck waiting again.

In practice, that means refilling a bit earlier and adjusting how much you add based on what’s still in the system from the previous cycle.

The easiest way to manage that, in our opinion, is to use a water level spigot instead of lifting the upper tank, which can be pretty awkward. That way, you can see exactly how much water is left in the lower tank at any time. Here’s an example installed on the Waterdrop King. Just like tank stands, these spigots are optional for most systems. Phoenix sells one — although it’s not all metal. Patriot Pure doesn’t seem to offer one, so you’d need a generic version and make sure it fits.

Based on average U.S. household usage, you’re looking at at least 1 refill per day, but more realistically 2 or more, depending on how much water you add each time.

Once you’re done, lid goes back on — that’s it. The lids on both Phoenix and Patriot Pure sit a bit loose, but they do their job. Some other systems, like BOROUX, have a tighter fit, which feels a bit more refined.

How about filter replacements?

These are easy, since the filter elements are readily accessible. The only real issue is that standard gravity systems don’t have filter life indicators, so you need to keep track of your water usage or estimate when it’s time to replace them. Each Patriot Pure Nanomesh filter is rated for 200 gallons. So if you’re using 2 in parallel, most households will likely need to replace them once or twice per year.

Taking everything into account, we ended up with a usability score of 4.22 for our custom combo, and 3.26 for the Patriot Pure Ultimate Water Filtration System. The biggest difference comes from the slower dispensing speed, and to a lesser extent, the overall setup and handling experience.

Alright, a few other things to keep in mind:

• First, the Phoenix system includes an airlock vent clip, which helps maintain consistent flow — and can actually make a real difference.
• Second, the Phoenix system is available in 4 sizes: 0.26, 1.5, 2.25, and 3.25 gallons.
• Third, systems at 2.25 gallons or above won’t fit under standard kitchen cabinets, which typically hang about 18 inches above the countertop. And that applies across the board, including the Patriot Pure.
• And fourth, both systems feel sturdy with their stainless steel tanks and are suitable for outdoor use. That said, our Patriot Pure unit already showed minor rust around one of the plugged holes. And the plastic spigot is likely the most vulnerable component. Otherwise, in terms of stored size and weight, both systems are very similar and in line with the rest of the competition.

For third-party customer feedback, the most common complaints we found about the Phoenix system were water bypassing the filter elements, leaking, and general quality issues.

For the Patriot Pure system — and Patriot Pure more broadly — the main complaints were leaking, delayed or incomplete shipments, and poor customer service. We didn’t run into any of those ourselves.

As for complaints specifically about the Nanomesh filter, the main ones were slow filtration and bad taste or odor.

That brings us to cost.

At the time of filming, the Phoenix Gravity Water Filter system costs $189 on Phoenix’s official website — link in the description. And if someone from Phoenix is watching: please give us a discount code for our viewers.

That $189 makes the Phoenix one of the most affordable systems in this comparison. But of course, that price doesn’t include any Nanomesh filters yet — it comes with 2 Phoenix carbon filters. And those actually finished third in our lab testing, just a little behind the Nanomesh filters, so not bad at all.

But if you want the full filtration performance of our custom combo, you’d need to buy at least 1 of Nanomesh filter separately. They come in different pack sizes on Amazon. At the time of filming, the smallest option was a 3-pack at $65.98 per filter. Larger packs bring that price down a bit — again, link in the description.

So total upfront cost for our custom combo — meaning the Phoenix system plus 2 Nanomesh filters — is $320.96. If you also add the water level spigot and tank stand, which aren’t mandatory but we do recommend, the total comes to $446.96.

That’s actually a little above average in our comparison, but it’s not surprising since you’re basically buying an extra set of filters.

On the plus side, the Phoenix tanks come with a 10-year warranty, which is much longer than any of the other systems except BOROUX. The standard Phoenix spigot is covered for 1 year, and all other parts for 6 months. On top of that, Phoenix gives you a 100-day satisfaction guarantee on the full purchase, and the package includes a free stainless steel water bottle.

Patriot Pure Nanomesh filters have a 1-year warranty, and the satisfaction guarantee is either 30 or 90 days depending on where you buy them. And one thing we haven’t mentioned yet: they’re claimed to be Made in USA.

As for long-term cost, using 2 filters in parallel, we estimate $165 per year based on 500 gallons of annual water use. That’s well below average in this comparison. And remember, that 200-gallon filter life rating is backed by actual NSF certifications — not just a bold manufacturer claim.

That gives our custom combo a cost score of 5.00 out of 5.00.

By comparison, the regular price for the old Patriot Pure Ultimate Water Filtration System — including 2 Nanomesh filters — was $295.93. Patriot Pure doesn’t offer a water level spigot, but it does offer an optional tank stand. That brings total upfront cost to $345.88, which is slightly below average.

Warranty is 1 year, plus a 90-day satisfaction guarantee.

And just like before, using 2 parallel Nanomesh filters, long-term cost comes out to around $165 per year. That gives the Patriot Pure a total cost score of 4.45 out of 5.00 — a bit lower than our custom combo, because we’re trying to rate value for money. So the main difference here really comes down to the 10-year warranty versus 1 year.

With filtration weighted at 60%, and usability and cost weighted at 20% each, the final ratings come out to 4.40 for our custom system #18 — making it the highest-scoring setup in the comparison, a great all-rounder, and our top recommendation if your priority is the most effective filtration — and 4.10 for the old Patriot Pure Ultimate Water Filtration System, which is still very solid and our runner-up for most effective filtration, just with lower usability.

One last note: of course we also tested whether Nanomesh filters would fit in the other systems we reviewed. We ran a good portion of a filtration cycle on each one to make sure there were no leaks and — aside from the Rorra and Santevia, of course — they all fit just fine. So if you already own one of those gravity filter housings, you should be able to use Nanomesh filters without any issues.

 

Okay, 2 more recommendations — starting with the Alexapure Pro, which is our top pick for non-potable water. Although that could change depending on how our real-world germ reduction testing turns out. So again, make sure you’re subscribed if you don’t want to miss that.

Quick disclaimer: boiling is generally considered the most reliable way to treat water of unknown quality, because it effectively eliminates bacteria AND viruses AND parasites. If boiling isn’t an option, you need a method — or a combination of methods — that targets all 3.Otherwise, there’s still a risk of getting sick.

We’ll go into more detail in part 2. For now, just keep in mind that there are 3 pathogen types you need to deal with.

Gravity filters handle this through size exclusion — meaning pathogens are physically trapped within the filter media or blocked at the surface. So you need a small enough pore size and/or complex flow paths to catch even the smallest ones: Viruses. According to the CDC, you’re looking at a required pore size of around 0.01 microns or smaller. But even if a filter claims that kind of micron rating, we’d still want to see proper test data confirming actual pathogen reduction.

And that’s where the Alexapure Pro stands out. It appears to be the only system in this comparison that’s been third-party tested according to NSF protocol P231 across its full 200-gallon rated filter life. And based on that testing, it qualifies as a microbiological water purifier under that protocol.

NSF protocol P231 is basically the benchmark here. And sure, official certification would’ve been even better than third-party testing. But based on the published lab report, the protocol seems to have been followed properly, and all requirements were met — including log-6 bacteria reduction, log-4 virus reduction, and log-3 cyst reduction. On top of that, the Alexapure Pro also reports 100% E. coli reduction from a separate test, which is nice to see as well. Does that guarantee you can safely use it on any water source? Probably not. In fact, the Alexapure manual says not to use it with microbiologically unsafe water or water of unknown quality without proper testing and/or disinfection before or after. They specifically recommend chlorine dioxide. So while we think the Alexapure Pro is as good as it gets for germ reduction with a gravity filter, they probably don’t want to take on that liability — which makes sense.

How about non-pathogenic contaminant reduction?

We tested the Alexapure Pro in both 2024 and 2026, with solid results — 2024 was just slightly weaker. We saw 100% removal of chlorine, all 4 disinfection byproducts, copper, barium, boron, nitrate, and uranium. Lower reductions were lithium at 0%, strontium at 24%, and fluoride at 20%.

In 2026, we saw 100% removal of chlorine, all 3 disinfection byproducts, iron, manganese, and boron. Copper, barium, and nitrate were all above 90%, so still very strong. Fluoride came in at 76%, which is a big improvement. Strontium again lagged behind at 28%.

One interesting point: in both years, we saw potential leaching of the same 2 substances — aluminum and silver. But in both cases, the levels were well below the strictest health guidelines, so not a concern.

So overall, solid lab performance — just slightly behind the Patriot Pure Nanomesh filter.

Taste and odor were also clean, no issues there.

Where the Alexapure clearly falls short compared to the Nanomesh filter is NSF certification — because there aren’t any. What it does have is extensive third-party testing— not just for microbial reduction as mentioned earlier, but also for dozens of VOCs, semi-volatiles, heavy metals, pesticides, herbicides, pharmaceuticals, chlorine and chloramine, fluoride, nitrate, uranium, radiologicals, and more.

The issue is, it’s not always clear how much of the 200-gallon filter life that testing actually covers. For example, gross alpha and beta, and uranium were only tested for 20 gallons.

So overall, a filtration score of 3.76 out of 5.00.

For usability, the Alexapure Pro is just as easy to set up as the Phoenix, so we won’t go through the whole process again. Instructions are clear, illustrated, and there’s also a tutorial on YouTube.

One thing to note: no faucet priming is required, since the filters arrive wet. That said, our 2024 filter didn’t process any water at first — we had to scrub it with a sponge to get it going. Minor issue, but worth mentioning.

In terms of speed, one filter needed 11 minutes 17 seconds to reach dispensing level at 44 ounces. From there, it took 2 minutes 6 seconds for one cup, 10 minutes 10 seconds for 4 cups, and about 3 hours 25 minutes for the full tank. With 2 filters in parallel — which the system supports up to 4 — filtration is noticeably faster than the Nanomesh setup, especially at the start. It does slow down more toward the end, but overall it’s still about twice as fast. And let’s not forget that more water fits into the Alexapure’s feed tank, so there’s simply more water being processed. Compared to the average across all systems, the Alexapure is clearly faster. So from a usability standpoint, it works well for daily use — even if on-demand filtering still takes some patience.

Dispensing is also extremely fast with the stainless steel spigot: about 2.5 seconds per cup from a full reservoir, just slightly behind the Phoenix. And like the others, you’ll need to move the system to the counter edge or use a stand. So we’d recommend the optional Alexapure stand or a compatible alternative.

For refilling, the instructions say to fill to about 1 inch from the top. Just make sure not to do that if there’s still too much water left in the 2.18-gallon lower tank. There’s no branded water level spigot, so you’d need a compatible third-party one.

The lid fits loosely, and just like before, you’re looking at at least 1 refill per day, but more likely 2 or more depending on usage.

Filter replacement is simple. No indicator, though. Each filter is rated for 200 gallons, so typical households will replace once or twice per year. One tip: if filtration slows down early, you can try scrubbing the filters to restore flow. But that doesn’t reset filtration performance — so we wouldn’t push beyond the rated lifespan, especially for non-potable water.

That gives the Alexapure Pro a usability score of 3.98 out of 5.00.

A few more quick notes:

• Alexapure Pro filters come with a rubber cap, which helps prevent them from drying out during longer periods of non-use.
• When assembled, the system doesn’t fit under standard kitchen cabinets.
• We like the look — the matte finish is clean and less prone to fingerprints.
• And lastly, the build feels solid. With 304 stainless steel tanks and spigot, it’s definitely suitable for outdoor use. It’s also fairly compact when taken apart and not too heavy, so portability is decent.

Looking at third-party customer feedback, the most common complaints were ineffective filtration, leaking, filters not reaching their claimed lifespan, and customer service issues.

We didn’t experience the first 2 ourselves and can’t really comment on customer service. As for filter lifespan, some of those complaints likely go back to when Alexapure used to rate their filters at 5,000 gallons per element — which we already considered unrealistic in our first gravity filter comparison video. To be fair, a lot of competitors made similar claims back then, and many still do. But Alexapure doesn’t anymore, which we appreciate.

Now, let’s talk cost.

Right now, the Alexapure Pro system with 2 filters is priced at $399.90. If you add the tank stand, that’s another $44.95. So overall, slightly above average in our comparison — and roughly in line with our custom combo, although that included a water level spigot at that price. We did reach out for a discount code but got denied. That said, if you want to support the channel, you’ll find our affiliate link in the description and comparison sheet. Warranty is 1 year, which is standard — but much shorter than Phoenix’s 10-year coverage.

For long-term cost, using 2 filters in parallel — also claimed to be Made in USA — we estimate about $245 per year. That’s about average overall, but noticeably higher than the $165 for Nanomesh filters. So it’s no surprise the Alexapure ends up with a lower cost score: 3.88 out of 5.00.

Final rating comes in at 3.83 out of 5.00.But again, the reason it’s one of our top picks is the verified microbial reduction. If that’s your main priority, it’s a very strong option.

 

Alright, so we’ve covered our custom combo + the Patriot Pure Ultimate Water Filtration System for most effective filtration, and the Alexapure Pro for germ reduction.

Last recommendation: the Phoenix system paired with its standard carbon filters. This is our top pick if you’re looking for the most budget-friendly option that still delivers solid filtration. And as you’ve seen, the Phoenix system also scored highest in usability. On top of that, filtration is very fast with these carbon filters.

Starting with lab results:

We saw full removal across most contaminants. The only ones not fully removed were manganese at 78%, barium at 69%, strontium at 2%, nitrate at 90% — still very good — and fluoride at 56%.There was also a tiny amount of potential silver leaching, but well below the strictest guideline. Overall, these were the third-best lab results in 2026.

Taste and odor were clean, no issues there.

In terms of NSF certifications, this setup only has 2, and neither is particularly significant. But it does come with extensive third-party testing for contaminants like lead, PFOA and PFOS, arsenic, chromium, nitrate, and VOCs. The only downside is that at least some of that testing wasn’t done across the full rated filter life. That gives it a filtration score of 3.80 out of 5.00.

By the way, we wouldn’t use the carbon filters on non-potable water. They don’t have any test data for that, and it’s not mentioned anywhere on Phoenix’s website.

Setup is very straightforward — same process as before, with the only extra step being priming the carbon filters under cold water for about 2 to 3 minutes.

Where they really stand out is filtration speed. Using 2 filters in parallel, the first cup was ready in 47 seconds after reaching dispensing level, and 4 cups in under 3 minutes. The full feed tank was processed in roughly 50 minutes, making it the third fastest system we tested. If you want even more speed, you can always use up to 4parallel filters.

Dispensing is just as fast as our custom combo — about 2 seconds per cup — since that depends on the housing, not the filter.

Refilling works the same as discussed earlier. And again, a water level spigot helps a lot here.

Filter replacement is simple, with each carbon filter rated for 12 months or 2,750 gallons. But honestly, compared to other filters like the Nanomesh with more or less full NSF certification, that number seems pretty optimistic. So assuming 500 gallons annual consumption and using 2 parallel filters, we’d say to replace once or twice annually.

That gives us a usability score of 4.50 out of 5.00.

Additional pros and cons that are mostly the same as with our custom combo:

• An airlock vent clip is included.
• At 19.45”, the system won’t fit under standard kitchen cabinets.
• The 2.08-gallon clean reservoir is more than enough for most use cases, but there are both larger and smaller versions available.
• It’s fairly lightweight and easy to store, so portability is good.
• Build quality feels solid with 304 stainless steel tanks and spigot.
• The carbon filters are cleanable, which can help restore flow rate.
• You get a free stainless steel water bottle.
• And overall, we liked the packaging.

Looking at third-party feedback, the most common complaints were ineffective filtration, water bypassing the filters, leaking, and general quality issues.

The system is $189 upfront and includes 2 carbon filters. Adding the optional stand and water level spigot brings the total to $315. You can save about $20 with a filter subscription. That’s slightly below average and includes the 10-year tank warranty. The spigot and carbon filters are covered for 1 year, and all other parts for 6 months. There’s also the 100-day satisfaction guarantee.

For long-term cost, we estimate about $129 per year using 2 filters – well below average – with a possible $10 discount through subscription.

That gives it a cost score of 5.00 out of 5.00.

Putting it all together, the final rating comes out to 4.18 out of 5.00 — driven by solid filtration, excellent usability — especially speed — and very competitive cost.

 

Alright, quick-fire round of the remaining systems — starting with the Rorra.

Lab results were solid, but still behind our top 4, with very low fluoride reduction at 4%.

What we do like is the amount of testing data available on Rorra’s website. It covers 100 to 120% of filter life, and they also say they’re working on official certifications. The downside is that most of it focuses on organics – which are important, but based on our experience, often easier to remove. What we’re missing are heavy metals —they only cover lead — and salts.

Taste and odor were clean. Filtration is also very fast, and it only needs about 2 ounces to start dispensing. However, dispensing is slower at over 8.25 seconds per cup in our test, and the tap must be held open.

There’s a stand integrated into the system. Refilling is easy thanks to the built-in water shortage indicator — the only system in this comparison with that feature. The lid also fits very well.

Filter replacement is easy, and there’s even a filter life indicator. That said, it appears to be a simple 90-day timer, so it may not be very accurate depending on usage.

For outdoor or non-potable water use, it’s a clear no. But the battery-powered design does improve portability. Just keep in mind the Rorra is heavier than most systems and has a larger footprint, even though both feed and clean water capacities are relatively small. On the plus side, at 17”, it does fit under standard cabinets.

Design-wise, it looks modern with a matte finish and feels very well built — but it’s also one of the more expensive options, especially long term. We estimate about $300 per year with an optional subscription discount. Final score: 3.68 out of 5.00.

Next, the Culligan Scout.

Contaminant reduction was fairly solid, but the lab detected methylene chloride in our filtered water above the strictest health guideline, and it wasn’t present before filtration.

Filtration was also the slowest we tested, taking over 7 hours for a full tank, with nearly 12 minutes for the first cup after reaching dispensing level. And the system is already maxed out with 2 filters, so no way to speed it up.

On top of that, filters are rated for just 50 gallons, making it by far the most expensive system in our comparison long term. Final score: 3.06 out of 5.00.

Right after the Scout ranks the Big Berkey — not tested with the original Black Berkey filters, since there’s still the EPA stop-sale order, but used with the Phoenix Gravity New Millennium Edition Filters, which are officially endorsed as a replacement.

Contaminant reduction was solid, but we saw potential chloromethane leaching above health guidelines, which disqualifies the filters for us – which is unfortunate, because filtration speed was actually the fastest we measured, meeting our definition of on-demand filtering.

Now, one interesting detail: the Phoenix Gravity New Millennium Edition Filters are obviously related to Phoenix’s standard carbon filters. Side by side, they look pretty similar, except for the writing on the plastic base. And contaminant reduction in our lab testing was also very similar.

What also stands out is the same 2,750-gallon filter life claim. And just as with the Phoenix carbon filters, we couldn’t find anything that clearly supports the New Millennium filters in that regard — especially not in terms of NSF certifications. The only certification we found was for chlorine and taste & odor reduction — and even that is rated at 1,050 gallons, not 2,750.

There is third-party testing, but nothing we found confirms performance across that full lifespan. And 2,750 gallons is a lot. With 2 filters, that’s 5,500 gallons — or about 11 years at 500 gallons per year.

But this isn’t just a Phoenix issue. A lot of filters in this category claim 3,000 to even 5,000 gallons without proper certification. By comparison, filters with verified testing across their full lifespan are usually rated much lower — around 50, 200, maybe up to 400 gallons. So definitely something to keep in mind.

Final rating for the Big Berkey with Phoenix Gravity New Millennium Edition Filters: 3.00 out of 5.00.

Moving on — here’s why we recommend using Phoenix carbon filters, but not the optional Phoenix POSTreat Steel Fluoride Reduction Filters:

When we first tested this setup, contaminant reduction was nearly perfect. But the filtered water report also showed elevated aluminum levels — well above the strictest health guideline. We then tested the same system again without the fluoride add-on filters — and saw no aluminum at all. So for us, the only reasonable conclusion is that the fluoride filters must be the source, which we assume are based on activated alumina.

If you watched our first gravity filter comparison, this will sound familiar. Back then, we tested Berkey’s Black filters with the optional PF-2 fluoride filters and saw very similar results — elevated levels of some form of aluminum after filtration.

We covered this in detail in that video, but briefly: activated alumina is generally considered relatively safe in small amounts because of its low bioavailability. Still, adding contaminants to your water goes against the whole point of filtration.

And beyond that, it’s not completely ruled out that long-term intake could increase aluminum levels in the body. Plus, the European Food Safety Authority says that, depending on water chemistry and how the media is manufactured, aluminum can leach from activated alumina.

So overall, too many uncertainties in our opinion — which is why we still don’t recommend using Berkey PF-2 fluoride filters, and we don’t recommend Phoenix POSTreat Steel Fluoride Reduction Filters either.

The exact same applies to the Waterdrop King, which we only lab-tested in 2024. Once again, we tested the standard filters together with the optional fluoride filters — and aluminum levels went through the roof.

But even without the fluoride filters, we wouldn’t recommend the Waterdrop King. Lab performance was simply too poor. And since Waterdrop told us they haven’t made any improvements, re-testing didn’t make sense. So our advice is to stay away. One thing we did like, though, was the water level spigot. Final rating: 2.30 out of 5.00.

We’d also advise you to stay away from the Purewell 2.25G, despite how popular it is on Amazon. In 2024, we tested it with the K-Series Black carbon filters plus the optional fluoride filters — and once again, we saw elevated levels of some form of aluminum. So for our recent round, we skipped the fluoride filters, and that issue disappeared.

The problem is, overall lab performance was still weak, with 8 out of 12 substances not fully removed. On top of that, there don’t appear to be any NSF certifications for contaminant reduction, and only very limited third-party testing. We’re also not impressed with the company’s website. There are inconsistencies in their claims — for example, bacteria reduction is listed as 99.999% in one place and 99.9999% in another. Same issue with parasites. So even though usability was solid — we especially liked the water level window in the lower tank — and costs are low, this is a clear “No” for us.

Next: BOROUX. We tested the 3-gallon BOROUX Legacy using BOROUX Foundation and Proactive Fluoride Filters.

First thing worth mentioning is the priming pump that came with our unit. It was a limited-time add-on and isn’t included anymore apparently, but it worked really well. So it would be great to see something like that offered again — ideally by more brands.

That said, we can’t recommend BOROUX due to potential benzene leaching in our lab testing above the strictest health guideline. The lab report also listed toluene, though that stayed below the strictest guideline. At least the Proactive Fluoride Filters worked as intended and didn’t show any aluminum leaching. Sadly, they aren’t compatible with Phoenix carbon filters. We also like the amount of third-party testing BOROUX provides, even if official certifications are mostly missing.

Other than that, the larger tank means fewer refills, and setup was easy thanks to clear instructions and 2 quick-start guides. One issue we noticed during use: when removing or placing the upper tank, the stainless steel covers on the fluoride filters can fall off. Once we figured out how to handle it properly, it wasn’t a big deal, though.

There’s a lifetime warranty on the tanks and a 101-day satisfaction guarantee. Still, none of that makes up for the poor lab performance. Final rating: 2.41 out of 5.00.

Almost done — next is British Berkefeld. In 2024, we tested the Ultra Sterasyl filters and got mediocre lab results. So this time, we switched to the Ultra Fluoride filters, hoping for broader contaminant reduction. And while performance did improve, it still wasn’t enough.

That said, we do appreciate that Doulton — the company behind British Berkefeld — provides third-party testing covering the full 400-gallon filter life. We also have testing for bacteria and cyst reduction, so we’ll definitely include the British Berkefeld in our upcoming germ reduction tests. But for now, based on tap water performance, it’s not a recommendation.

Alright, the Santevia Gravity Water System. Setup is more involved — for example, you need to boil the mineral stones – but everything is straightforward.

The filtered water had a pleasant mineral taste, but lab results were mediocre and also showed potential leaching, which is why we didn’t re-test in 2026. Filtration is also very slow, and you can’t use more than one filter at a time. On top of that, the system is made entirely of plastic and has a relatively large footprint. So overall, not among our favorites.

Second to last, the Radiant Life SS Gravity Countertop Filter. This one had the worst lab performance of all. A flat zero — and it would’ve actually scored negative if our scale allowed it. The reason is potential leaching of methylene chloride, chromium, molybdenum, and vanadium (all below their strictest health guidelines), and arsenic at more than 600 times above the OEHHA guideline. Now you could argue that said guideline is very strict, but even the EPA has a maximum contaminant level goal for arsenic of 0. So with results like that, this is an easy one to skip.

And last, the ProOne Traveler+, which we tested in 2024 using a G2.0 5″ filter. But at this point, it doesn’t really matter. ProOne gravity systems have been discontinued following the acquisition by Culligan.

 

Alright, to wrap things up, I’d like to remind you that you can find our full analysis of all 18 gravity filter configurations, including lab reports, in the comparison sheet linked below. You’ll also find product links and any available discount codes there if you’re considering one of these systems.

And if you found this helpful, consider subscribing and giving the video a like. Feel free to drop your questions in the comments, share your experience with any of these filters, or let us know which ones you’d like us to test next.

Thanks for watching — and we’ll see you in the next one.