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Aquasana Review – OptimH20 RO System Tested

Derek Hales

Written By: Derek Hales

Updated on:

COUPON: Save 50% off any whole house & drinking systems with code AQMC50.

High-performance RO system

Aquasana Ro System

Aquasana RO System

The Aquasana RO system is an under-the-counter water filtration solution for your home. It offers a 4-stage filtration process, which filters out most harmful contaminants. In our analysis, the Aquasana greatly improved the quality of the water both in aesthetics and health. Setup can be complicated or require a plumber, but continued maintenance is quite simple.


  • Fantastic health and aesthetic filtration performance
  • Easy maintenance
  • 3 color options to choose from


  • Setup is complicated by yourself
  • 3 gallons of wastewater produced for every 1 gallon purified


RO with Healthy Water & Fantastic Taste
  • Design - 97%
  • Performance - 98%
  • Quality - 98%
  • Usability - 96%
  • Value - 94%


For healthy and tasty water, look no further than the Aquasana RO. Laboratory testing showed that the Aquasana was able to remove the vast majority of harmful materials in our unfiltered water, making it much safer to drink. In addition, it greatly improved the taste and feel of the water, receiving a 99/99 score from TapScore. Maintenance is incredibly simple for the device, and it comes in 3 color options.

In This Review

Purification Test | Filters | Waste Water | Filter Cost | Usability | Size | Summary

Purification Test

For our purification test, we used SimpleLab, who provides a water testing service called TapScore. They send you a kit to sample your water and return it for laboratory analysis.

Best Water Pitcher Filters Tapscore Boxes
Tap Score boxes

They provide detailed reports on the health, aesthetic, and plumbing impact of your water.

In addition to collecting water samples from the Aquasana RO system, we also took a sample from our softened unfiltered tap water. We use this other measurement as a baseline to compare the Aquasana’s results with.

Aquasana Faucet 1
Aquasana Faucet 1

Below is an overview of how Aquasana’s filtered water performed based on 3rd party laboratory analysis.

Health Risk


Plumbing Risk


Taste & Aesthetics


The comparison of the unfiltered vs. Aquasana filtered results helps us further see purification performance.

ContaminantsUnfiltered waterAquasana RO waterAquasana Removed
Total THMs3.5 ppb0.0 ppb100%
Chloroform3.5 ppb0.0 ppb100%
Molybdenum0.0047 ppm0.0 ppm100%
Uranium0.0039 ppm0.0 ppm100%
Nickel0.0 ppm0.0033 ppmadded
Selenium0.0019 ppm0.0 ppm100%
Manganese0.0 ppm0.001 ppmadded
Copper0.196 ppm0.0 ppm100%
Strontium0.978 ppm0.0 ppm100%
Nitrate0.5 ppm0.0 ppm100%
Barium0.111 ppm0.0 ppm100%
Boron0.128 ppm0.0 ppm100%
Zinc0.0 ppm0.036 ppmadded

Health Risk Analysis

The health risk report showed positive results for the Aquasana RO system. Our unfiltered water, in comparison, showed many materials that could negatively impact a person’s health. It can impact:

  • Kidney health
  • Liver health
  • Developmental outcomes
  • Immune systems
  • Gastrointestinal systems
  • Reproductive systems
  • Blood systems
  • Nervous systems
  • Cardiovascular health
  • Skeletal health

In comparison, most of these materials were removed by the Aquasana and if any remained, it did not exceed the benchmark to impact health.

Healh Impact Materials Ppb
Health Impact Materials PPB

These graphs show a comparison between the unfiltered water and water filtered by the Aquasana. These graphs don’t include all the information provided by TapScore, but rather the information that most impacted health. You can view the complete laboratory report and analysis here.

Health Impact Materials Ppm 1
Health Impact Materials PPM
Health Impact Materials Ppm 2
Health Impact Materials PPM

You can view the complete laboratory report and analysis of the unfiltered water here, and the Aquasana RO here.

Aesthetic Risk Analysis

The aesthetic results for the Aquasana RO were also fantastic. TapScore provides the user with a score from 1-99 with 99 being the best score, and for aesthetic performance, the Aquasana received a 99.

Aesthetic is all about the taste and feel of the water, so having a lower score isn’t necessarily a bad thing, like our unfiltered water.

Aesthetic Impact Materials Ppm
Aesthetic Impact Materials PPM

In contrast, the unfiltered water had high levels of sodium, magnesium, and sulfate, all which impact taste and feel.

Ph Comparison
pH Comparison

Only trace amounts of these materials were detected in the Aquasana’s water, if it wasn’t completely filtered.

These graphs show the comparison between unfiltered water and the Aquasana.

Plumbing Risk Analysis

Plumbing is where the Aquasana RO struggled the most. However, these issues apply to piping and aren’t typically relevant for an RO system installed at the sink. Due to it being installed under the sink, none of its filtered water flows through the piping in your home. Therefore it will have no impact on your home’s piping.

Plumbing Impact Materials Alkalinity
Plumbing Impact Materials Alkalinity

Regardless, alkalinity was low for the Aquasana and the chloride to sulfate mass ratio was very high.

In contrast, our unfiltered water showed normal levels of Alkalinity, but had a moderate chlorine to sulfate mass ratio and very hard water.

Aquasana vs. Waterdrop vs. Brita (& 7 Other Popular Brands)

We previously worked with SimpleLab to test many popular water filters for pitchers. Below is a table comparing the scores we received for those pitchers to the scores we received for Aquasana

ContaminantsAquasana ROSorso RO waterAquaTru ClassicWaterdropEpicWaterAmazon BasicsBritaPURZeroWater
Total THMs100%100%100%100%100%100%100%100%40.6%
Nickeladded 0.003100%100%100%100%100%100%100%100%
Selenium100%100%100%100%100%100%100%Added 0.0021 ppm100%
Lead100%100%100%100%100%100%100%Added 0.0007 ppm100%
Nitrate100%100%100%Added 0.2 ppm100%100%100%100%100%
Zincadded 0.03100%100%100%100%100%100%100%100%

The Filters

Aquasana sells a few different versions of their under-the-counter RO system. Depending on which version you choose, you may have less or more filters included. We tested the OptimH2O Reverse Osmosis + Claryum, which comes with a 4-part filtration system. This includes:

  • Activated carbon filter
  • Reverse osmosis membrane
  • Claryum or catalytic carbon
  • Remineralizer

First, the activated carbon filter filters out organic materials like VOCs, pesticides, and more.

Aquasana Carbon Filter
Aquasana Carbon Filter

Next, the main reverse osmosis membrane will filter dissolved solids and help remove fluoride, arsenic, nitrites, and radium.

Aquasana Ro Filter
Aquasana RO Membrane
Aquasana Claryum Filter
Aquasana Claryum Filter

The water then flows through the catalytic carbon filter, what they call Claryum, which filters out more organic chemicals and chlorine.

Aquasana Remineralizer
Aquasana Remineralizer

The final filter is the remineralizer, which adds back materials to the water like calcium, magnesium, and potassium. In addition, it helps balance the pH and alkalinity levels.

Filter Replacement Cost Analysis

We also analyzed how much it costs per gallon of water purified and compared it to other filters and water solutions. These numbers are based on 600 gallons of water a year filtered or the manufacturer’s recommendation.

Filter Cost Analysis
Filter Cost Analysis

Aquasana falls somewhere on the more expensive end of the spectrum, but not by much. That said, it is still notably cheaper than other options.

Please note: this is a strict comparison of the price of the filter or purified water option, and the amount of drinkable water you get from it. We don’t factor in the cost of the one time costs of the system itself, just the replacement filters.

Waste Water Test

Reverse osmosis systems create wastewater during the filtration process. The amount of waste water produced can vary depending on the system itself.

Some have a worse ratio of 10 : 1 meaning they produce 10 gallons of wastewater for every 1 gallon of purified water produced. In other cases, the best RO systems promise a 1 : 1 ratio.

Aquasana Tank
Aquasana Tank

Due to the system complexity of the purified water reservoir, we were unable to test exactly how much waste water it produced. That said, Aquasana states it has a 3 : 1 ratio, meaning it will create 3 gallons of wastewater for every 1 gallon of purified water.

This isn’t as bad as it can get, however, if wastewater is a major concern for you may want to consider another RO system.

Usability Tests

Usability for the Aquasana is quite good. It is an under-the-counter RO system, which is great for those who want to maximize counter space and has 3 color options.


Setting up the Aquasana RO system is complicated. It requires the use of tools as well as some basic plumbing knowledge. Aquasana states that it will require drilling into your pipes and if that isn’t something you are comfortable with they recommend hiring a professional plumber.

Aquasana Unboxed
Aquasana Unboxed

That said, if you do wish to install the device yourself, they have a detailed manual and video to assist you in installation. 

Aquasana Under Sink
Aquasana Under Sink

Once the RO system is installed, you will need to flush the system. This can be done by letting water flow through the Aquasana for 24 hours before first use. 


Maintenance for the Aquasana is quite simple, really only requiring the use to replace the filters as needed. 

Activated Carbon & Claryum

6 months

RO Membrane

12 months


12 months

Replacing the filters is quite easy, simply requiring you to untwist the filters, and screw in the replacement. 

Aquasana Filters With Holder
Aquasana Filters With Holder

As a reminder you will want to make sure to flush the filters after replacement before drinking water. 

Size & Dimensions

As the Aquasana RO is an under the counter system, most of its bulk is hidden from view. That said, you will need some space under the sink for the tank, and filters. 

The part you see most often is the faucet on top. It comes in three different colors you can choose from when purchasing.

These include:

  • Brushed nickel
  • Chrome
  • Oil rubbed bronze

We received the oil rubbed bronze, which is nice and is easy to use. Simply by twisting the handle the flow of water can be started or stopped. 

Aquasana OptimH2O vs. 3-Stage Max Flow vs. 3-Stage vs. 2-Stage

Aquasana has multiple RO systems to choose from depending on your needs. 

ModelOptimH2O3-Stage Max Flow3-Stage2-Stage
Faucet TypeDedicated FaucetDedicated FaucetDedicated FaucetDedicated Faucet
Filter Capacity265 gallons800 gallons600 gallons500 gallons
Flow Rate0.5 gal/min0.72 gal/min0.5 gal/min0.5 gal/min
Number of Contaminants Removed88777777

Their top of the line is the Optim H2O, which we tested. This system comes with the full 4-stage filtration system.

Aquasana 3 Stage Max Flow
Aquasana 3 Stage Max Flow

The next option, the 3-Stage Max Flow, has similar filters with a larger filter capacity, but no Remineralizer. 

If filter capacity isn’t as important of a factor, the 3-Stage offers the same filters as the Max Flow, but with less capacity and a smaller size. 

Aquasana 2 Stage
Aquasana 2 Stage

Finally for 2-Stage, you have less capacity, a smaller size, and one less filter.

Should you buy the Aquasana RO System?

I would recommend the Aquasana RO System if you are looking for the following features:

  • Healthy and tasty drinking water: The laboratory testing showed that the Aquasana RO provides not only healthy water, but water that tastes good as well. The majority of harmful contaminants were removed from the water and other materials were removed or added to improve the taste and feel. 
  • Easy to replace filters: While maintenance can sometimes be a challenge for RO systems, it is quite the opposite for the Aquasana. Replacing the filters is incredibly easy. With one twist you can remove them, and with another the filter is replaced.

For more information or to buy the Aquasana RO System, click here.

About Derek Hales

Derek HalesDerek Hales is the Founder and Editor-in-Chief of He has been featured in Fast Company, Reader's Digest, Business Insider,, She Knows, and other major publications. Derek has a Bachelor's Degree in Business Administration from Kansas State University. Hales has been testing and reviewing products for the home since 2014.

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2 Comments on “Aquasana Review – OptimH20 RO System Tested”

  1. Two questions: Is the same system really 250 on amazon and 350 on their direct website? That seems odd. Also I could only find the brushed nickel version on amazon. Is there the same thing but with chrome sold there too ? Thanks

    • That does seem to be the case.

      On their website they have the “water for life” package, which signs you up for their subscription to replace the filters automatically, and that price is $250.

      Looks like they are just really trying to push people to sign up for that.