BOROUX Legacy Review: Lab Analysis & Hands-On Testing

Full Analysis of the BOROUX Legacy with Foundation + Proactive Fluoride Filters

Filtration: 1.10/5.00

The BOROUX Legacy scored 1.10/5.00 for filtration. How? Most importantly, it achieved very poor results in our 2026 lab testing though the filtered water tasted perfectly clean with no odor. Plus, it has only 2 NSF/ANSI certifications for contaminant reduction (for particulates and microplastics). While it has extensive third-party testing covering more than 85 impurities, the tested volumes vary considerably depending on the contaminant.

1. Lab Results: 1.25/5.00

In our lab test comparing an unfiltered and a filtered tap water sample, the BOROUX Legacy could remove 8 undesirable impurities and contaminants to below the minimum detection level (so essentially to 100%): chlorine, dibromochloromethane, copper, boron, strontium, iron, manganese, and fluoride.

The following substances remained in our water (note: in our view, most concentration increases are generally due to leaching, although natural fluctuations cannot be ruled out):

• Bromodichloromethane was reduced by 93%. BOROUX’s third-party test data claims 98.36% (calculated average) bromodichloromethane reduction.
• Chloroform decreased by 85%. BOROUX’s test data reports 98.36% chloroform reduction.
• Barium was reduced by 91%.
• Nitrate was reduced by 95%.

Aside from contaminant reduction, we found the following substances in our filtered water that were not present in the unfiltered water:

• Molybdenum. At 2.47 ppb, it was 16.19x lower than the strictest molybdenum health guideline we could find (EWG, 40 ppb). While molybdenum is an essential trace mineral, excess amounts may be harmful. Associated effects above the EWG guideline include changes in blood chemistry, including increased uric acid levels, which may lead to gout-like symptoms.
• Toluene – At 1.73 ppb, it was 34.68x lower than the strictest toluene health guideline we could find (60 ppb, Health Canada). Associated effects above that guideline include damage to the nervous system. BOROUX’S third-party test data claims 98.36% (calculated average) toluene reduction.
• Benzene – At 1.41 ppb, it was 9.40x higher than the strictest benzene health guideline we could find (0.15 ppb, California OEHHA). Associated effects above that guideline include an increased risk of cancer, especially leukemia. BOROUX’S third-party test data reports 98.36% (calculated average) benzene reduction.

Lab Results Chart

2. NSF/ANSI Certifications and Other Test Data

The BOROUX Legacy is certified by the WQA for the reduction of 2 contaminants against NSF/ANSI standards 42 and 401. These certifications include nominal particulate class I (98.90%) and microplastics (98.90%). Reduction rates are per the official performance data sheet.

It also has extensive third-party testing against NSF/ANSI standards 42, 53, 401 and other non-NSF/ANSI standards for more than 85 contaminants. However, contaminants were tested to different final volumes, ranging from 50 to 6,000 gal (most to 200 gal) using a single filter element.

Reduction rates include:

• Chlorine (98.64% – calculated average)
• Chloramine (97.70% – calculated average)
• Chloroform (surrogate for VOCs, including most of the listed DBPs, pesticides/herbicides & industrial chemicals: 98.36% – calculated average)
• Chromium 6 (83.89-86.77% – calculated averages for pH 6.5 & pH 8.5)
• Glyphosate (93.81% – calculated average)
• Fluoride (78.97% – calculated average for 500 gal)
• Lead (98.85% – calculated average for 4,000 gal, pH 6.5)
• Mercury (94.24% – calculated average for 350 gal, pH 6.5)
• Mercury (92.68% – calculated average for 900 gal, pH 8.5)
• Uranium (98.94% – calculated average for 350 gal, pH 6.5)
• Gross beta (cesium; 97.85% – calculated average for 50 gal)
• Total PFAS (99.47% – calculated average)
• TCEP (>96.90% – calculated average)
• TCPP (97.51% – calculated average)

Calculated reduction rates are based on the testing of a single Foundation filter element (with a single Proactive Fluoride filter for fluoride testing) per the BOROUX Legacy’s official performance data sheets (1, 2).

3. Filtration Process

BOROUX Legacy Foundation filters are made from a “specialized blend” of activated carbon block infused with silver. Activated carbon removes things like bad tastes and odors, chlorine/chloramine, disinfection byproducts and other organics, as well as certain metals. In addition, the block structure provides fine mechanical filtration due to its smaller pore size compared to granular carbon. Silver is added to support the hygiene of the filter by inhibiting microbial growth.

The Proactive Fluoride filters are made of granular activated carbon with a nano-carbon outer layer. As noted above, activated carbon removes certain impurities via adsorption. This filter also performs some degree of mechanical filtration: per the manufacturer, “The micropores of the nano-carbon exterior prevent contaminant molecules from flowing through.” It’s possible that the Proactive Fluoride filters utilize bone char, a form of activated carbon known for its fluoride-reducing abilities.

4. Taste and Odor Test

In our test, the filtered water was odorless and had a perfectly clean taste.

Usability: 4.21/5.00

The BOROUX Legacy achieved a usability score of 4.21/5.00, based on its performance in the following categories:

1. Initial system assembly including filter priming (1.00/1.00)
2. Everyday use (3.01/3.50)
3. Filter replacements (0.20/0.50)

1. Initial Setup & Filter Priming: 1.00/1.00

Assembling the BOROUX Legacy is easy thanks to the clear, detailed instruction booklet plus two quick-start guides. The materials are well-organized with plenty of illustrations. There’s also a helpful tutorial video on YouTube. Plus, our unit came with a complementary automatic filter primer, which made priming very convenient and much easier than priming via the tap. However, this was a limited time offer and may not be applicable to future purchases.

Here’s a quick breakdown of the setup procedure:

1. Wash the chambers and other parts (excluding the filters) by hand using warm water and a mild dishwashing soap. Rinse and dry.
2. Insert hole plugs into upper chamber holes which will not be housing filters.
3. Leaving one washer on the hole plug, insert plug through hole inside upper chamber. To the exposed portion, add the second washer, then screw on wingnut to hand-tight.
4. Repeat with remaining hole plug, installing it diagonally from the first one.
5. Attach silicone ring to the lower chamber, aligning its notch below the spigot hole.
6. Remove the wingnut, stainless steel washers, and silicone washers from the spigot.
7. Thread one SS washer followed by a silicone washer onto spigot, then insert through hole in lower chamber.
8. Thread the remaining silicone and SS washers onto the spigot inside the lower chamber, and secure in place with the wingnut.
9. Turn spigot handle to closed position.
10. Remove the wingnut and washer from each BOROUX Foundation filter.
11. Foundation filters may be primed using the automatic filter primer (if available), the blue silicone priming tool, tan priming tool, or water bottle.
12. Using the included blue silicone priming tool: attach the tool to the faucet, pulling it up as far as possible to create a good seal.
13. Turn on tap and adjust the cold water flow so that a 12 oz cup fills within 45 to 60 seconds. While the water is running, push stem of filter into the blue primer.
14. If the blue primer inflates or leaks excessively, re-adjust the water flow per the above recommendations.
15. Once water beads appear on filter surface (1-2 min), continue to prime for another 1 to 2 minutes, until entire filter surface is wet.
16. Repeat the process for the other Foundation filter(s).
17. Place rubber washer onto the stem of each Foundation filter. Insert the filter stem into an empty hole on the inside of the upper chamber.
18. On the outside of the chamber, screw the wingnut onto the filter stem and hand tighten.
19. Repeat for remaining filter(s).
20. Remove paper wrapping from fluoride filters; remove plug from the filter’s cap. Screw threaded priming adapter into the filter.
21. Prime fluoride filters using the same method as for the Foundation filters described above.
22. Remove threaded priming adapter from fluoride filter.
23. Remove wing nut from the foundation filter. Place black silicone washer on this filter stem, then screw a fluoride filter onto the stem. Do not over-tighten.
24. Repeat for remaining fluoride filter(s), then install a stainless steel shell onto each fluoride filter.
25. Place the upper chamber onto the lower chamber.
26. Fill the upper chamber with cold or room temperature water just to the top of the foundation filters; cover with the lid.
27. Filter water and discard.
28. Refill and allow the BOROUX Legacy to filter the water. Now your system is ready to use.

2. Day-to-Day Use: 3.01/3.50

2.1 Speed & Water Capacity: 0.96/1.20

Used with two Foundation and two Proactive Fluoride filters, the BOROUX Legacy is generally suited for daily use but on-demand filtering, which we define as 1 cup in <1 minute, takes just a little more patience. The system filtered and dispensed 1 cup in ~1:55 min and 4 cups in ~8:01 min in our filtration speed tests. However, it can accommodate up to four filter elements in parallel, which would roughly double filtration speed relative to the two-filter setup tested here and permit on-demand dispensing.

That said, as the spigot sits above the bottom of the lower chamber, the system must process and collect ~42 oz of water before any can be dispensed, which took ~10:41 min. As a result, starting from an empty system, the total time to filter and dispense 1 cup was ~12:36 min, while dispensing 4 cups took ~18:42 min.

Requiring ~3:32 hr to fully filter and dispense the entire feed tank, the BOROUX Legacy produces large volumes relatively quickly for a gravity system. It’s definitely fast enough to handle 8-10 cup/hour thirst bursts for average US households, which we assume consist of 2.55-3.15 people.

Dispensing filtered water from a full lower reservoir is also very fast – we measured about 4.25 seconds for 1 cup.

The very generous 2.45-gal (~39.2-cup) feed tank* and 2.78-gal (~44.5-cup) clean tank allow you to easily fill a 40-oz bottle or 2-quart pitcher from a single refill. Assuming 25.5–31.5 cups of daily water consumption for the average US households, we estimate only 1 daily refill when filling the upper chamber to the top* – less than the 1-2 daily refills for the other gravity systems we tested. This makes sense, since the BOROUX Legacy is larger and rated at 3 gal, while most of the other gravity systems we tested were rated at 2.25 gal.

However, actual refilling frequency will likely vary considerably depending on each household’s needs and preferences. Given the relatively slow filtration speed inherent to gravity systems, most users likely would not want to wait until the feed tank is empty and the clean water fully depleted before refilling. Realistically, it is more practical to top off the feed tank at strategic times, such as before heading out to work or before bed, so the longer wait time is less disruptive. However, this requires some ongoing judgment from the user to ensure that the added feed water volume does not cause the clean tank to overflow.

2.2 Dispensing: 0.95/1.00

Using a full clean tank, dispensing water is very fast and without splashing, even when the spout is fully opened all at once. The handle twists smoothly, and there is no dripping after the pour.

Due to the spout height, the system must be placed at the counter edge to dispense, unless you use the optional tank stand sold by the manufacturer – this gives you another 6″ of clearance to fit a glass underneath. That said, you still won’t be able to fit a standard 40-oz bottle or 2-quart pitcher under the spout, even with the added height from the stand.

One minor grievance: dispensing the last 42 oz of water requires additional steps. The spigot sits slightly above the base of the clean tank, which means the last ~5.25 cups of water cannot be poured unless you are tilting the tank forward or manually ladle out the remaining water. However, this is a common limitation and applies to almost all gravity filters we tested.

2.3 Refilling & Size: 0.90/1.00

Refilling the BOROUX Legacy is straightforward. Simply use a pitcher or other container to fill the upper chamber with water. There are no max fill lines, but the instructions say to fill completely.

The included lid fits perfectly to keep your feed water well protected.

Plus, an optional water level spigot can be purchased separately from BOROUX for easy monitoring of your clean water level, which we highly recommend. Without it, the only way to accurately gauge the amount of water in the clean tank is to lift the upper chamber – a bit of a chore depending on how much water remains inside.

Measuring 9″x23.25″x10.75″ (WxHxD) including the lid and spigot, the BOROUX Legacy doesn’t fit under most kitchen cabinets (18” clearance). Additionally, using the optional tank stand further increases the height.

At 11 lbs with two wet Foundation filters and two saturated fluoride filters installed (excluding the stand), its weight is about average for the gravity systems we tested with analogous configurations. Its footprint is also about average, occupying ~63.62 in² (~0.44 ft²).

2.4 Other: 0.20/0.30

The BOROUX Legacy system includes a rubber ring on the bottom tank, preventing scratching or sliding on your counter tops. Plus, the optional tank stand has rubber-gripped feet to prevent unwanted movement.

However, depending on your technique, removing or replacing the top tank can cause the stainless steel fluoride filter covers to fall off, which is a minor irritation. After a bit of practice, we adjusted the way we lifted the upper chamber (no tilting), and they stayed put just fine.

2.5 Outdoor Use

With 304 stainless steel tanks and spigot, the BOROUX Legacy is durable enough for outdoor use. It even comes with a canvas tote for transportation.

Its stowed size of 9″x15.25″x9″, (WxHxD; spigot removed) is not as compact as competing systems, which might make it relatively less portable. However, its 11-lb weight (with two wet carbon filters + two saturated fluoride filters installed, excluding the stand) is comparable to the other gravity filters we tested — especially when you take its larger capacity into account.

3. Filter Replacements: 0.20/0.50

Filter replacements are simple as the cartridges are easily accessible. However, there is no filter change indicator to alert you when it is time to change them.

Rated filter life is 12 months per pair of Foundation filters and 1,000 gal per pair of fluoride filters.

Assuming 500 gallons of yearly water consumption for the average household, we predict you will have to replace the Foundation or fluoride filter pairs once yearly or every two years, respectively.

Costs: 4.53/5.00

Based on value for money, the BOROUX Legacy incl. optional tank stand, optional water level spigot, two Foundation filters + two fluoride filters achieved a cost score of 4.53 out of 5.00, indicating it is priced below average for what it offers compared to competing systems (a score of 4.00 represents average value). Notably, its upfront price is well above average while its annual filter replacement costs are slightly below average compared to the other gravity filter systems we tested.

1. Upfront Price

As of March 6, 2026, the BOROUX Legacy including two Foundation filters + two fluoride filters is priced at $485. Adding the optional water level spigot ($65) and tank stand ($40) brings the upfront total to $590, which is well above the $384.81 average across all the tested gravity filter systems.

2. Long-Term Expenses for Filter Replacements

Based on 500 gallons consumption, a 12-month filter life for two Foundation filter elements and a 1,000-gal filter life for two Proactive fluoride filter elements, we estimate $210 in annual filter replacement costs, which is slightly below the $234.50 average across all the tested gravity filter systems. Plus, you can save $31 with a Foundation filter subscription and receive 17.5% off the fluoride elements with a fluoride filter subscription, assuming you only replace the cartridges and not the stainless steel covers as well.

3. Product Warranty

The BOROUX Legacy system and Foundation filters come with a lifetime or 1-year warranty, respectively. The manufacturer also provides a 101-day satisfaction guarantee for both, though a $16 return fee applies.

The fluoride filter cartridges and shells are covered by a 6-month or lifetime warranty, respectively; both feature a 60-day satisfaction guarantee, subject to the $16 return fee.

4. Other Cost Factors

Nice canvas tote allows you to take the system on the go.

Additional

1. Construction

The system feels sturdy and well built, with 304 stainless steel upper/lower tanks and spigot. We appreciate its attractive, simple appearance: the domed lid is knob-free for a cleaner look, and the spigot handle adds an elegant touch.

2. Size & Color Options

The BOROUX legacy comes in 2 sizes: the 1.8-gal (Compact) or 3.0-gal (Legacy). You may also choose from 4 color options.

3. Cleanable Filters

You can remove and scrub the Foundation filters using an abrasive sponge (such as a 3M Scotch Brite pad) while running under water. This helps to restore the flow rate, which may slow over time due to mineral buildup. The manufacturer recommends doing so every 3 to 6 months or when you notice slowed filtration.

4. Nice Extras

In addition to the complementary automatic primer, our unit came with a free glass pitcher, though it was advertised as a limited time offer.

5. Thoughtful Packaging

The BOROUX Legacy is shipped in very nice, eco-friendly packaging. All components are carefully nestled in protective fabric sleeves or customized inserts or boxes.

6. Frequent Customer Complaints

We read about priming issues, bad taste of the filtered water, and filters clogging rapidly.

We did not experience these problems firsthand.

Bottom Line: User-Friendly but Filtration’s a Letdown (2.41/5.00)

Filtration weighted at 60%, and usability and cost at 20% each, the BOROUX Legacy with 2 Foundation filters + 2 Proactive Fluoride filters scored a final rating of 2.41 out of 5.00.

Unfortunately, overall filtration performance was very poor. On a positive note, the system completely removed 8 contaminants in our lab tests and produced filtered water that tasted and smelled perfectly clean. And while it only has 2 NSF/ANSI-certified contaminants (particulates and microplastics), it has extensive third-party testing for more than 85 impurities (albeit to varying volumes). The biggest detractor, however, is the potential leaching of benzene at a 9.40x higher level than the strictest health guideline. It also showed potential molybdenum and toluene leaching, though both were below their respective guidelines.

On the other hand, the Legacy’s usability is solid: it’s beautifully packaged, and very simple to setup and maintain, with cleanable Foundation filters that are easy to replace (no filter life indicator). Our unit even came with a complementary automatic primer, which was so much easier than fussing with the tap. The system also filters plenty of water fairly quickly, taking ~3.5 hours to process a full feed tank, and only requires 1 daily refill for most households. Plus, you can add up to 2 more parallel elements to increase filtration speed.

We really like the elegant spigot handle, which allows for very fast dispensing with a full clean tank – there’s no splashing, even when the tap’s quickly opened to full flow. The optional tank stand makes pouring into a cup easy, and the rubber ring on the bottom tank and grippy feet on the stand ensure the system won’t slide around on your counter.

Refilling is also straightforward as long as you purchase the optional water level spigot to monitor clean tank contents – particularly because we found the fluoride filter shells can get knocked loose if you aren’t careful when lifting the feed tank.

Overall build quality is very good with the durable 304 stainless steel tanks and spigot. Plus, it’s stowable and comes with a canvas tote for portability, making it suitable for outdoor use, though dimensionally it’s a tad bigger than some of the other tested systems. A lifetime warranty (system + fluoride filter shells, excluding the filters) and 60 to 101-day satisfaction guarantee depending on the components also provides peace of mind.

While upfront price is well above average, ongoing filter replacement costs come in slightly below average. Despite reasonable value and user-friendly features, we’d still pass on the BOROUX Legacy in favor of gravity systems that don’t potentially leach hazardous chemicals.