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– RO Water Filtration System Expansion Tank – 3 Gallon Water Tank -– Compact Reverse Osmosis Water Storage Pressure Tank with Free 1/4" Tank Ball Valve

  • Based on 468 reviews
Condition: New
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$39.99 Why this price?
Save $12.00 was $51.99

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Availability: In Stock.
Fulfilled by Amazon

Arrives Friday, Jul 4
Order within 9 hours and 56 minutes
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Features

  • Reverse Osmosis Tank: Made from 100% food grade materials, this RO water tank stores and keeps your water free from any impurities and harsh chemicals. The perfect addition to any RO water system.
  • Easy to Install Water Tank: RO tank replacements include free tank ball valve for easy set-up and replacement with 14 quick connect design.
  • Durable Water Storage Tank: This RO water tank is rigorously tested for quality and durability and includes a 1-year warranty.
  • High Quality Water Tank: This water storage tank is made from durable deep-drawn steel domes with precision welding to ensure long lasting value for your RO water system.
  • Water Tank Dimensions: This compact water tank is designed (14 x 9 x 9) to fit under most kitchen sinks. Stores up to 2.2 gallons of water for on-demand filtered drinking water.

Brand: tankRo


Special Feature: Durable


Product Dimensions: 9"L x 9"W x 14"H


Package Information: Tank


Installation Type: Under Sink


Power Source: Adapter


Model Name: GTS3


Upper Temperature Rating: 1E+2 Degrees Fahrenheit


Supported Water TDS Level Maximum (PPM): 2000


UPC:


Brand: ‎tankRo


Special Feature: ‎Durable


Product Dimensions: ‎9"L x 9"W x 14"H


Package Information: ‎Tank


Installation Type: ‎Under Sink


Power Source: ‎Adapter


Model Name: ‎GTS3


Upper Temperature Rating: ‎1E+2 Degrees Fahrenheit


Supported Water TDS Level Maximum (PPM): ‎2000


UPC: ‎653590999287


Manufacturer: ‎tankRo


Part Number: ‎GTS3


Item Weight: ‎5.94 pounds


Country of Origin: ‎Taiwan


Item model number: ‎GTS3


Is Discontinued By Manufacturer: ‎No


Size: ‎9" x 9" x 14"


Color: ‎White


Item Package Quantity: ‎1


Special Features: ‎Durable


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: February 21, 2018


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Jul 4

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • I would buy this product again.
Really appreciate that there were instructions with the RO tank. The tank works like a charm.
Reviewed in the United States on September 3, 2024 by Tootsie H.

  • It's smaller than our old tank
Water filter for osmosis.. works great...it doesn't take 5 minutes to fill my cup...
Reviewed in the United States on September 9, 2024 by Vicky Hertz

  • tankRO – RO Water Filtration System Expansion Tank
I cant give a five star as I just baught it last one lasted 7 years but started to slow way down from what I have seen these last 2-5 years its a replaceable part that just wears out thats why I always have a spair on hand looks to be a good tank.
Reviewed in the United States on July 10, 2024 by us army ltc 05

  • Just What The Doctor Ordered
I replaced my Nimbus Watermaker 5 tank. It was 11 years old and wasn't doing the job. After filling a water glass, the flow slowed to a trickle. This was very easy to install. The included 1/4" valve was too small, so I just used my old valve. Now I have great flow to all three RO dispensers. Make sure you verify the pressure is 6-7 lbs before you install. ... show more
Reviewed in the United States on October 19, 2024 by M. Clare M. Clare

  • Fit perfectly, and is reasonably priced.
Easy to install and great value for the money. Though it has a smaller capacity than the one it replaced, we still have plenty of pressure and water available for our daily needs. In addition, other reviewers have stated that it did not last as long as they had hoped for compared to the OEM tank, we will monitor to see if in fact that is the case, and update the review as necessary. ... show more
Reviewed in the United States on February 1, 2024 by Signetring54

  • Alls good
It arrived on time without damage and works.
Reviewed in the United States on January 5, 2025 by Starr

  • Great Purchase
I recently bought this replacement tank for my whirlpool reverse osmosis because all of the whirlpools would only last about two years in a tank would begin to lick. Just wooden hole pressure. This replacement tank from Amazon is a fantastic well well-made TANK with a whole lot less money. I picked up the extended warranty probably won’t need it. If you need one, I recommend one from Amazon. ... show more
Reviewed in the United States on October 2, 2024 by Rusty

  • Taste good
Easy replacement. Works as expected
Reviewed in the United States on June 30, 2024 by Al P

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