This page contains affiliate links. Learn more.
Our Verdict (Best For)
The Aquasana Claryum 3-Stage Max Flow (aka AQ-5300+) is easy to set up, use, and maintain. Plus, it’s space-saving and, based on our speed test, offers fast flow from the dedicated faucet. However, we also found some design flaws: The filters didn’t lock solidly in place, and the housing top popped off when moving the unit. Also, the overall quality of the under sink water filter isn’t as good as with other systems we’ve tested. And while the Aquasana holds NSF certifications for 77 contaminants which is great, they’re mostly easier-to-remove organics. Still, filtered water tasted and smelled perfectly clean, and in our lab testing, we saw mostly good contaminant reduction – but also one red flag: Chloromethane appeared in our filtered water more than 27 times higher than the strictest health guideline. Bottom line: There are better under sink filters for that price.
The Aquasana Claryum 3-Stage Max Flow (aka AQ-5300+) is an under sink water filter that requires a plumbing connection and comes with its own faucet. It’s designed for use as a drinking water filter and can purify both tap water and properly disinfected well water.
As usual, we’ve tested the system with our own hands:
- Hands-on experience: We installed/assembled, used, and maintained it.
- Filtration effectiveness: We sent an unfiltered and a filtered tap water sample to a professional lab for analysis in order to determine real-life contaminant reduction capabilities. Plus, we checked for NSF certifications and other test data.
- More testing: We performed a taste & odor test and a filtration speed test.
- All other product aspects: We considered initial + long-term cost, product warranties, additional features, frequent customer complaints, etc.
Contents
Final Rating: /5.00
FiltrationFiltration score combines our lab results and taste testing with NSF/ANSI certifications and 3rd-party contaminant reduction data.: /5.00
Usability: /5.00
CostsCost scores reflect overall value for money rather than price alone.: /5.00
| Type: | Under Sink Water Filter |
| PriceNo short-term sales. (May 5, 2025): | $449.99 (Use Code AQBOS50 for Up to 50% Off!) |
| Yearly CostEstimate is based on rated/claimed filter life and 1,000 gallons annual water consumption. No short-term sales. (May 5, 2025): | ~$175 (Save 15% With Filter Subscription) |
(Use Code AQBOS50 for Up to 50% Off!)
Final Rating: /5.00
What We Like Most
- Achieved mostly good results in our lab testing for contaminant reduction.
- Filtered water tasted and smelled 100% clean.
- High count of NSF-certified contaminants (but limited in regards to contaminant types mostly covering “easier-to-remove” organics).
- Easy to set up, prime, and use.
- Simple, space-saving design with 4 faucet options to choose from.
- Very fast flow from dedicated faucet.
- Easy to maintain with provided filter wrench to help remove filters.
- Filter life indicator.
- 90-day satisfaction guarantee.
What We Don’t Like
- Chloromethane (73.22 ppb) appeared in filtered water way above strictest health guidelines.
- Filters don’t lock solidly into place when screwed in, and housing top pops off when moving the unit.
- Faucet and feed water adapter don’t use quick-connect fittings, taking a few extra steps to connect.
- Overall quality not as good as similar systems.
- 3rd-party customers complained about extremely slow faucet flow, leaking (tubing popping out, broken filter housings, failing O-rings), and sediment filters being too short.
How the Aquasana Claryum 3-Stage Max Flow Compares to…
18 Other Under Sink Water Filters
In this video, Sara highlights our under sink water filter top picks. The Aquasana Claryum 3-Stage Max Flow was included in our testing, but didn’t make the cut.
Please note: Our full guide on the best under sink water filters is available here.
Video Chapters + Comparison Sheet
- Link to Comparison Sheet
- 00:00 – Intro
- 00:34 – How We Tested & Rated
- 01:53 – Our Recommendations
- 03:01 – Best Overall (Cloud RO)
- 15:11 – 2 Best Tankless ROs (Waterdrop G3P600 & X12)
- 27:26 – Best Non-RO Filter (Epic Smart Shield)
- 31:22 – Highest Filtration Score (Aquasana SmartFlow)
- 32:02 – Made in USA (USWS All American & Home Master TMHP-L)
- 32:34 – Budget RO Pick (APEC ROES-50 Essence)
- 32:51 – AO Smith AO-US-200 & Culligan US-EZ-4
- 33:34 – Summary
Full Analysis of the Aquasana AQ-5300+
Filtration: /5.00
1. Lab Results: /5.00
Remember that our before vs after lab comparison is not an exact science. It’s informational and subject to variability, inaccuracies, and interferences caused by natural fluctuations in water quality, accidental contamination, human error, instrumentation issues, and more. Furthermore, our lab-testing is limited to those contaminants present in our water supplies and at their respective concentrations. As such, it can only give us a general idea for how effective a certain water treatment product might be.
Lab Results Chart
| Potentially Harmful | Aesthetic Issues | Feed Water Level | Filtered Water Level | Reduction Rate | |
| Water Disinfectants | |||||
| Chlorine (mg/L) | ✖ | ✖ | 1.22 | 0 | 100% |
| Disinfection Byproducts | |||||
| Bromodichloromethane (µg/L) | ✖ | 2.04 | 0 | 100% | |
| Bromoform (µg/L) | ✖ | 1.86 | 0 | 100% | |
| Dibromochloromethane (µg/L) | ✖ | 2.82 | 0 | 100% | |
| Chloroform (µg/L) | ✖ | 1.07 | 0 | 100% | |
| Metals | |||||
| Copper (mg/L) | ✖ | ✖ | 0.04 | 0 | 100% |
| Barium (mg/L) | ✖ | 0.04 | 0 | 100% | |
| Boron (mg/L) | ✖ | 0.06 | 0.03 | 50% | |
| Lithium (mg/L) | ✖ | 0.01 | 0 | 100% | |
| Strontium (mg/L) | ✖ | 0.42 | 0.18 | 57% | |
| Salts | |||||
| Nitrate (N) (mg/L) | ✖ | 1.96 | 0 | 100% | |
| Fluoride (mg/L) | ✖ | 0.58 | 0.57 | 2% | |
| Other | |||||
| Uranium (µg/L) | ✖ | 1 | 0 | 100% | |
| Impurities NOT Detected in Unfiltered Tap Water Sample | |||||
| Chloromethane (µg/L) | ✖ | 0 | 73.22 | ||
| Explanation: | |||||
| Full Removal | |||||
| Considerable Reduction | |||||
| Concentration More Than Double of Unfiltered Water Sample | |||||
| Potential Leaching Reached or Exceeded the Strictest Public Health Guideline We Could Find | |||||
*100% means reduction to below the minimum detection level. To learn more about our testing procedures check our editorial guidelines.
Link to Filtered Water Report
Link to Unfiltered Water Report
Usability: /5.00
Costs: /5.00
Please note: This page is still a work in progress. Additional content and details will be added shortly – stay tuned!
Further Reading
About the Author(s)
Sara has been a lifelong home-improvement fan (she’s been hooked on This Old House since she was five) and taught herself any project she didn’t already know by watching YouTube tutorials. She is also an award-winning filmmaker. Armed with this skillset, Sara installs, primes, samples, uses, and maintains nearly every point-of-use water treatment systems we test – then brings her results to life on camera for our YouTube channel.
Raoul has a background in mechanical engineering and has been writing about home water treatment since 2015. He designs our product review processes, analyzes the results, and ties everything together. As editor-in-chief, he tries hard to keep the whole operation running smoothly behind the scenes.