Aquasana AQ-RO-3.55 OptimH2O RO System Review – Want a Tasty Water with the Essential Minerals?


OUR RATING: (4.5/5)

The biggest concern people have when it comes to reverse osmosis water filtration is the hanging question around drinking demineralized aqua. No matter where you turn to online you will find many people arguing it is detrimental towards our health and just as many arguing that it has little to no effect. In a perfect world, we should get all these minerals from our food supply, but busy as we are, that’s rarely the case.

What isn’t in doubt, however, is that our body needs these minerals for various functions and for general health. Whatever the source may be. It should then be with relief that you find out about a RO filtering complex that replenishes the minerals lost during the process. More specifically the Aquasana AQ-RO-3.55 OptimH2O Reverse Osmosis Fluoride purifier.

Let’s look at this product in more detail and review it for you so you can make the best decision for you.


NSF/ANSI Standards 42, 53 & 58

Standard 42 means it’s certified to remove particles that taste or smell. Standard 53 means that it’s certified to filter out contaminants that have negative health impacts. Standard 58 ensures that it’s actually a RO H2O complex certified product.


3-stage filtration system

Like most systems the Aquasana AQ-RO-3.55 has 3 stages of filtration.



This system replenishes essential and healthy minerals that are lost during reverse osmosis.


2-gallon storage tank

3.2 Gallons is not the biggest but adequate for a family’s daily drinking needs.


4 faucet styles

Choose the look and feel that suits the rest of your home and satisfies your taste. You can choose from brushed nickel, chrome, oil rubbed bronze, and chrome metal.


5 gpm flow rate

While this definitely isn’t the fastest on the market it should just be enough if you let your system fill up over night.

Pros and Cons


Remineralization neutralises the only negative to a RO system.


Better PH balance leads to a better taste.


Reduces much more fluoride and other substances than most other systems.


It runs a bit slow compared to other systems. Many buyers state it isn’t as fast as Aquasana claim.


It only produces 17.91% of the aqua that’s filtered which isn’t very efficient.

AQUASANA AQ-RO-3.55 – How Does It Work?

RO systems are consisted of three-stage arrangement that is most common structure of purifiers.

Each stage filters out different contaminants and the end result is pure, crystal clear drinking H2O. The only problem is you lose many healthy minerals too.

This is how the Aquasana goes about the process of remineralizing your drinking water after osmosis:

The 4-Stage System


First of all, the aqua goes through the AQ-RO3 Carbon filter that removes carbon and chlorides. These largely contribute to the bad taste or odor.


The Aquasana has a special stage 3 with the trademark Claryum filter which removes an additional 60 contaminants. Including pesticides and herbicides.


This is the main stage of any reverse osmosis system, where the liquid passes through the RO membrane. This is where most contaminants and particles are removed. Aquasana guarantees the removal of 14 contaminants with their RO membrane. Including fluoride, nitrates, lead, and arsenic.


Now, we get to the Aquasana’s star feature. The remineralization. This is done through a special remineralizer that replenishes calcium, magnesium, and potassium. The addition of these minerals also makes the H2O more PH balanced by reducing acidity which improves the taste as well.

So, What’s Our Impression?

Well, first of all, it’s hard to say exactly how big a difference the remineralizer makes to your health. This topic is still up for debate. However, we can say that you definitely taste the difference. The water is definitely less acidic and has that almost (but not really) sweet taste that is refreshing.

Although the machine definitely doesn’t run as fast as other competitors (even some we have reviewed). This shouldn’t cause you too much grief if you don’t empty the storage tank in a single day. Maybe it would have been nice if this specific system had a slightly bigger storage tank. If you aren’t satisfied with this particular design you can check out rest of the reviews on

All in all though, it’s still a very good filtration system and the remineralization isn’t just some sales gimmick, you really taste the difference. Whether, it’s really more beneficial for your health is debatable, but it definitely couldn’t hurt.

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