Aquatic Life Color Changing Mixed Bed Resin Filter Cartridge, 21-CI

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$22.50 (-20%) Chewy Price
$27.99 List Price
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About This Item

Details

  • Cation and anion resins (H+ and OH-) remove the remaining total dissolved solids from the water.
  • Resins change from blue to amber when the media is completely exhausted.
  • Clear design allows you to easily see the color changing, taking the guesswork out of when to change.
  • ¼-inch tubing easily attaches to the press-to-fit connections on each end of the cartridge.
  • Includes mounting clips to make it easy to attach to any standard-sized reverse osmosis (RO) membrane housing.

Instructions

Learn More About Aquatic Life From Our Team of Experts

Questions & Answers

1 Customer Questions

Can this be attached to a regular RO buddie 3 stage? It would I have to buy the 4 stage?

Answer by Chewy • Dec 19, 2018
This is able to attach to both the Aquatic Life RO Buddie Three Stage Osmosis System and the Aquatic Life RO Buddie Four Stage Osmosis System.
Reviews
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3.1
Rated 3.1 out of 5 stars
12 Ratings
Terms & Conditions

10 Customer Reviews

Rated 5 out of 5 stars
By Ornel on Apr 9, 2025

Works great

I use this for my reef and planted tanks. The output from the auto-topoff is always single digit PPM. Have purchased this now 4 times and will continue to buy. Great

I use this for my reef and planted tanks. The output from the auto-topoff is always single digit PPM. Have purchased this now 4 times and will continue to buy. Great product.

Rated 1 out of 5 stars
By Luis on Jan 3, 2021

Ro filter Refill

This thing only last me like 10 gallons and it was completely discolored, the original that came withe system last me a lot longer

This thing only last me like 10 gallons and it was completely discolored, the original that came withe system last me a lot longer

Rated 2 out of 5 stars
By Puckhog on Nov 24, 2020

Works but Does Not Last

I get about 60 to 90 gallons and then it’s spent. Works great but it doesn’t last.

I get about 60 to 90 gallons and then it’s spent. Works great but it doesn’t last.

Rated 2 out of 5 stars
By MCAR on Nov 20, 2020

Very limited filter

I bought this filter to add to my RO system and I didn't get more that 60 gallons out of it before it was not filtering properly. I wouldn't buy this again. I have

I bought this filter to add to my RO system and I didn't get more that 60 gallons out of it before it was not filtering properly. I wouldn't buy this again. I have to take it off my auto ship for every 6 months.

Rated 1 out of 5 stars
By KRISH on Oct 26, 2020

NOT WORTH 1.89

AFTER ABOUT 7 GALLONS THIS THING WAS DONE, DONT WASTE YOUR MONEY ON THIS, COMPLETLY NOT WORTH IT

AFTER ABOUT 7 GALLONS THIS THING WAS DONE, DONT WASTE YOUR MONEY ON THIS, COMPLETLY NOT WORTH IT

Rated 1 out of 5 stars
By gerg on Nov 4, 2019

Chinese Junk

Product is inconsistent with quality of parts. Ordered 1 and product IS NOT packed tightly into canister, thus causing permeate to flow around media. Also permeate

Product is inconsistent with quality of parts. Ordered 1 and product IS NOT packed tightly into canister, thus causing permeate to flow around media. Also permeate incoming was at 8TDS, unit only lasted 60 days at roughly 1.5 gal p/day. Second canister was missing the plastic cap at the top, thus pushing the foam into the exit port and causing DI media to flow out. Again, this is cheap Chinese product, poor R&D and worst quality control.

Rated 3 out of 5 stars
By Joseph on Aug 5, 2019

Works great but doesn’t last

Mine only made about 75 gallons before it was spent. Wished it would have lasted longer as these cartridges are not cheap.

Mine only made about 75 gallons before it was spent. Wished it would have lasted longer as these cartridges are not cheap.

Rated 3 out of 5 stars
By John on Feb 16, 2019

Damaged product from Box

Check these cartridges very carefully. Mine came with a cracked end and leaked RO water all over the floor. Plastic cant be repaired and cant stop the leaking.

Check these cartridges very carefully. Mine came with a cracked end and leaked RO water all over the floor. Plastic cant be repaired and cant stop the leaking.

Rated 4 out of 5 stars
By zeus on Jul 30, 2018

aquatic life

Great product but finishes too quickly. This product is more for back up and mobile RODI.

Great product but finishes too quickly. This product is more for back up and mobile RODI.

Rated 5 out of 5 stars
By Cin55 on Mar 24, 2018

Just a little extra..

Thank you, the cartridge is going strong, made 100's of gallons so far and the color is a third changed...so it works great....My Discus and German Blue Rams appreciate

Thank you, the cartridge is going strong, made 100's of gallons so far and the color is a third changed...so it works great....My Discus and German Blue Rams appreciate it very much...reasonably priced...