Pressurized Water Storage Tank - Reverse Osmosis Water Tank with Stainless Steel Connections and Ball Valve - Water Filtration System Storage Tank 10 Gal & appx. 6 Gal Usable Capacity (ROT-10-W)

This is listed appx 6 gallons usable. This is dependent on incoming water pressure. I have a regulator on my home water line set at 70psi and after all night refill after the second flush of the new tank I measured the amount of RO water the thank holds at 70 psi fill pressure, which was 3.75 gallons. This is to be expected with these type of tanks. There is a diaphragm in the center with 8 psi of nitrogen or just air depending on the manufacture below and your incoming RO water on top. The incoming water pressure pushed the diaphragm down against the gas pressure. When you used the water the gas pushes the diaphragm up sending the water out the faucet. With the narrow tall shape I assume the diaphragm is closer to the top as it must be completely pushed up to the outlet when empty of water. The placement of the diaphragm (surmising) reduces the amount of water that the thank can hold compared to a short stout tank. This is fine for me, I needed the narrow tall tank to fit my space and it has more than doubled what the 3.x gallon tank could provide, which it replaced. If incoming water pressure is more than 70 psi (max is 100 for this tank) I would bet it holds closer to what is advertised. This was a simple swap with the existing tank and does everything it is supposed to do. Just keep the fact you will probably NOT get 6 gallons our of this tank especially if you are on a well or other low pressure system. Hope that helps set expectations and you are not disappointed.

Its so much better having a 10 gallon compared to the typical 3 gallon. We've used it for a week now with no issues.

Measurements are way off. Tank is not 12in diameter, but 14in. Won’t fit. Non returnable. Total waste of money.

Easy to setup. Bought the 10 gallon to upsize a 4.5 gallon. Very easy to swap out and then let it fill and drain 3 times before using. The extra capacity is exactly what we needed for a family of 5, and sometime a few guests.

No surprises, works

Added the necessary capacity to RO system after factory tanks diaphragm's failed

I have bi ro unit that feeds my sink in the kitchen an fridge, Adlai have a tee so that I can fill bucket for my plants. Dose what it’s suppose to

Quality unit no doubt, however, the advertising says 6gal. My initial test shows it ran out of water after 5gal. Still better than the little 3gal, but not 6. Perhaps this will change as the unit is broken in.