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– RO Water Filtration System Expansion Tank – 6 Gallon Water Tank -– Compact Reverse Osmosis Water Storage Pressure Tank with Free 1/4" Tank Ball Valve

  • Based on 557 reviews
Condition: New
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Returnable until Jan 31, 2025

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Availability: In Stock.
Fulfilled by Amazon

Arrives Wednesday, Jul 2
Order within 2 hours and 12 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 (17.5 x 12 x 12) to fit under most kitchen sinks. Stores up to 4.4 gallons of water for on-demand filtered drinking water.

Brand: tankRo


Special Feature: Durable


Product Dimensions: 12"L x 12"W x 17.5"H


Package Information: Bottle


Installation Type: Under Sink


Item Weight: 11 Pounds


Model Name: GTS6


Upper Temperature Rating: 212 Degrees Fahrenheit


Supported Water TDS Level Maximum (PPM): 50


UPC:


Brand: ‎tankRo


Special Feature: ‎Durable


Product Dimensions: ‎12"L x 12"W x 17.5"H


Package Information: ‎Bottle


Installation Type: ‎Under Sink


Item Weight: ‎11 Pounds


Model Name: ‎GTS6


Upper Temperature Rating: ‎212 Degrees Fahrenheit


Supported Water TDS Level Maximum (PPM): ‎50


UPC: ‎653590999294


Manufacturer: ‎tankRo


Part Number: ‎GTS6


Item Weight: ‎11 pounds


Country of Origin: ‎Taiwan


Item model number: ‎GTS6


Is Discontinued By Manufacturer: ‎No


Size: ‎12" x 12" x 17.50"


Color: ‎Blue


Style: ‎6 Gallons


Item Package Quantity: ‎1


Capacity Description: ‎4.4 Gallons


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: Wednesday, Jul 2

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.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


  • Why did I not already have one???
Why did I not already have one of these?? It is so nice having this large resevoir so I can fill pasta pots, dog bowls, kids sports tumblers, etc. without having to stop part way thru and wait for it to refill. It fits nicely under my sink, but note that I have a center sink drain. It may not fit under a double sink with 2 drains. Measure twice before purchasing. Again, why did I not purchase one of these 15 years ago???? ... show more
Reviewed in the United States on November 26, 2024 by Scott Swanbery

  • Excellent upgrade to our original, inadequate tank.
Great upgrade to our RO system. We exclusively drink our RO water through an alkaline/mineral cartridge to optimize taste. We use around 3 half gallon bottles per day for drinking and making coffee. We also have a whole house steam humidifier and a large bar ice maker that are fed from our RO system. This tank easily stores enough water for all of our needs. Easily fills over 2 gallons at a time while our original tank could only fill around 1. Easy hookup, great quality, no added taste or smell...excellent tank and a great buy. ... show more
Reviewed in the United States on May 14, 2020 by T. Pariseau

  • Better than having our water system company do it
I was glad to get our old tank replaced. It works as it should and was a fair value
Reviewed in the United States on November 17, 2024 by pashcha

  • Good tank but be weary of included valve
2nd tank like this I've had. After delivery, I checked pressure and even through transit, pressure was still at 7 PSI which is awesome. Replaced defective tank and after two days found that the included valve is seeping water between handle and body. Old valve already by picked up by trash dude. Had to order one since HD, Lowes, and Ace don't carry it locally. Waiting game. Would recommend having a better valve on hand during install/replacement. ... show more
Reviewed in the United States on November 24, 2024 by Wally

  • Great upgrade for my RO system
I’ve had a RO system for many years and had a smaller tank on it. The bladder finally went and I decided to upgrade and it is performing very well. I followed the instructions to clear the tank after one minute of operation and then again after four hours of operation. There is no residual taste. When hooking it up to your system, I would make sure to just leave the pressure where it’s at as it is typical for most systems. If it doesn’t work for you then adjust it. Furthermore, when you put the Plastic valve on the top, I would use not only Teflon tape but also some dope as well. I had to return the first tank they sent as it was not wrapped well and came dented, but to be fair it did work for the short period of time before a replacement was sent, the company was quite responsive. As an FYI, the second tank came much better wrapped. It was undamaged. they had clearly realized they had a problem so they change the wrapping. ... show more
Reviewed in the United States on December 21, 2024 by Father of 4

  • Good pressure
Came charged at the correct PSI and install was simple. I simply unthreaded the old tank and used the same connection to connect to this tank (make sure to add teflon tape). We bought this to replace a 3-gallon tank that came with our system; this thing blows that tank out of the water...heh. The previous tank would severely slow down after about a half-gallon. This tank has more pressure and it maintains it pretty well even after 3+ gallons are quickly used. Overall, I am happy with the purchase because we now always have enough RO water when we need it (we use the RO water for the plants as well as for drinking). Others complained about a bad taste, ours was fine. After install we waited 4+ hours and drained the entire tank like the directions instruct. ... show more
Reviewed in the United States on February 14, 2021 by Adam

  • We'll say it's better than my 3 Gallon tank
Packaged nicely. Quick shipping. Discovered a rather large dent upon opening and contacted seller. Agreed to accept return, but I agreed that it should not be a problem and kept it. Trouble getting more than 3 gallons from this 6 gallon tank. Reduced pressure from 10.5psi to 6psi and it appears better. Will test again later. Took awhile to get rid of the special flavor, bur after a month or so it's negligible now. Overall I'd give this product an average rating for value to cost. Update 10/4/21: lowered rating to 2 stars due to false advertising. I have never gotten more than 3.3 gallons out of this advertised 6 gallon tank. Now a dissatisfied customer. Update 08/31/24: down to 1 star. Bottle lasted less than 3 years. Less and less water. Have emptied and repressurized, max out at less than 2 gallons. Membrane obviously failing. Buy at your own risk. I've ordered a new one from another company. ... show more
Reviewed in the United States on August 5, 2021 by A. Farmer A. Farmer

  • Probably the best tank for the money.
Other tanks with non-serviceable pressure ports will lose pressure over time.
Reviewed in the United States on November 1, 2024 by 98northwood

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