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Home > Reverse Osmosis Storage Tanks > Amtrol RO Metal Pressurized Tanks

Amtrol (141S351) RO Steel Pressure Tank 4.4 Gallon 1/4" NPT White

Amtrol (141S351) RO Steel Pressure Tank 4.4 Gallon 1/4" NPT White


Retail Price:: $89.93

Your Savings:: $32.94

On sale: $73.34$56.99 On Sale


Availability: Ships within 24-72 hours

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AMTROL has been manufacturing Reverse Osmosis Water Storage Tanks for over 4 decades. Not only have we been doing it longer than anyone else, we actually invented the technology behind RO tanks.

Our proven technology, vast experience and countless other qualities are what place AMTROL high above other manufacturers with their look-alike tanks. Remember, looks can be deceiving. And in the end, you always get what you pay for.

Fully enclosed polypropylene and butyl water reservoir ensures water purity, and there's less rubber/water contact than with a bladder tank.

AMTROL's pioneering diaphragm design provides longest life and most complete water discharge.


  • Made in USA
  • Unsurpassed customer service
  • Expert technical support
  • ISO Certified
  • All models NSF Listed
  • Industry's most comprehensive five-year warranty
  • AMTROL invented technology
  • 4 decades
  • CE
  • Fittings: 1/4"
  • Size: 4.4 Gallons
  • Storage Capacity: 2.8 Gallons
  • Diameter: 11" Dia. x 15" Height


4.4 Gallon Amtrol tank
I had purchased a complete 4 stage RO system with a Taiwanese tank. When received new the tank wasn't pressurizing the water properly, and when I tried to check the air pressure in the tank, water was forced out of the air valve. So the new bladder had a hole in it somewhere. I ended up taking 3.1/2 litres of water out of the "air" side of the bladder, but not only that, about 20% was fine rust particles. I decided then that I would never consider another Taiwanese tank and only wanted the best. So, based on their reputation, I imported the Amtrol tank from America. The tank is doing everything I expect of it, but being realistic, I can't really comment on how good it is until I find it is still working correctly in 8 to 10 years.
Reviewed by: Barry Blackman from Perth, Western Australia. on 3/9/2013
Great tank
I bought this tank to replace another brand that was slightly smaller. This tank came with the right amount of pressure in it, and leaves no taste to the water. Couldn't be happier. Quick delivery too.
Reviewed by: Todd from Norco, CA. on 12/23/2012
orchid grower
Amtrol tanks are high quality and manufactured in the US. I have 4 Amtrol tanks in service now for my home and greenhouse RO system. Some have been in service for 2 years with no problems. Isopure ships promptly and accurately.
Reviewed by: David Campen from Los Angeles California. on 9/20/2012
Longest Life
It was time to finally replace my tank but these tanks last a really long time. I am using my old tank for almost 8 years......It provided great pressure water until now without any problem. I just purchased this brand again and I'm really happy it arrived so quickly.\
Reviewed by: Moc Rany from Provo, Utah. on 3/30/2012


Questions & Answers

Q: Am replacing an Amtrol RO-314os723 tank, Will this work as a replacement, There is room under the sink for this tank?
Asked by:  - 3/15/2014 (Submit an answer)
A: Yes. It will work and should fit a standard kitchen sink cabinet.
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Q: I have a Nimbus Sierra RO filter come with a 2G capacity pressure tank. Can I replace the tank with the Amtrol 4.4G tank?
Asked by:  - 4/21/2014 (Submit an answer)
A: Yes
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Q: Will amtrol141s351 ro steel pressure tank 4.4 gallon one-quarter inch npt white fit a ultima 7 reverse osmosis 5 stage water system with a 3.2 gallon tank with brass fittings?
Asked by:  - 8/2/2014 (Submit an answer)
A: Yes it will work and should match just fine.
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