Arrow Fat Left Icon Arrow Fat Right Icon Arrow Right Icon Cart Icon Close Circle Icon Expand Arrows Icon Facebook Icon Instagram Icon Pinterest Icon Twitter Icon Hamburger Icon Information Icon Down Arrow Icon Mail Icon Mini Cart Icon Person Icon Ruler Icon Search Icon Shirt Icon Triangle Icon Bag Icon Play Video

Aquasana Under Counter Reverse Osmosis Water Filter - AQ-RO3

$399.99 $279.99

Aquasana Under Counter Reverse Osmosis Water Filter - AQ-RO3

$399.99 $279.99

Sold out

We're sold out, so buy the Aquasana 4 stage Reverse Osmosis (RO) system directly from the manufacturer by clicking here.

If you want to remove fluoride, nitrate, arsenic and other hard to remove contaminants and want the convenience of a separate faucet with the cleanest water possible, this is one of your options.

Your other option is a new water filter that changes everything! The Propur Promax Countertop and Propur Promax Under Counter Water Filter Systems. These water filters perform as well as an RO system with a much lower cost. Learn more here

The Aquasana Reverse Osmosis (RO) Water Filter System carries NSF 42, 53, and 58 certifications and is certified by NSF to remove 74 contaminants. Aquasana uses their “Claryum” filtration technology to remove chlorine and chloramines, VOC’s including TTHM’s, lead, mercury, MTBE; and the RO filter to remove arsenic, fluoride, nitrate and nitrite, radium 226/228, and the other “RO only” contaminants.

Made in the USA.

Why NSF Certifications are Important

If you are evaluating other Reverse Osmosis water filter systems, be sure to ask if the filters have certifications for 42, 53 & 58 by NSF which is an independent third party tester. Also, ask for a copy of the test report. The report will show you what percentage of each contaminant the filter removes.

Some systems aren't as effective as others. We selected this RO system as the best because it had three certifications by a third party and the test results were better than other systems tested. We've read hundreds of test reports and this filter's results really stood out. View the test report at the bottom of this page.

This RO System Remineralizes Your Water

Some have expressed concern that the effectiveness of RO filters causes them to remove some desirable minerals such as calcium, magnesium, and potassium from your drinking water.

To counteract this, Aquasana includes a “remineralization” component after the RO filter that adds these desirable minerals back into your filtered water.

If you'd prefer not to have an RO system remove and then remineralize your water, you have other options that are highly effective at removing contaminants. Check out the Propur Promax Countertop and Propur Promax Under Counter Water Filter Systems. These water filters perform as well as an RO system with a much lower cost. Learn more here

Why Choose Reverse Osmosis?

Reverse Osmosis filter systems offer the highest level water filtration available for home use. In addition to the activated carbon filters, a Reverse Osmosis system employs a Thin Film Composite (TFC) membrane capable of removing many toxic contaminants other methods cannot, such as Arsenic (pentavalent), Barium, Fluoride, Nitrate and Nitrite, Perchlorate, Radium 226/228, and Selenium. Reverse Osmosis filters carry their own, specific NSF certification, 58. The best systems and the only ones you should consider will also have NSF certifications 42 and 53, and remove all of the key contaminants we have been tracking in our previous filters.

Because of the science behind Reverse Osmosis, these systems require a separate holding tank (2-5 gallons) that you will need space for, and also produce waste water so they will need to be tied into your drain. Most systems come with “quick-connect” attachments making DIY installation possible, but it will be more involved than a regular under the counter filter and you will probably need a plumber. It's typically a 1-2 hour job.

  • Filter Life: 6 months-2 years
  • Filter Cost: $23.99-$64.99
  • Filter Media: carbon, ion exchange/RO
  • Flow Rate: 0.5 GPM

Have more questions? Call us at 1-800-221-5109 or email us.

Want to see the Aquasana RO system test results? Click here for the full test report!