What is a Reverse Osmosis Tank and How Does it Work?


A reverse osmosis tank is a hydropneumatic pressure tank designed to fit beneath the sink and inline with your reverse osmosis system. The reverse osmosis tank is a storage tank, collecting the water being gradually purified by the reverse osmosis membrane. The reverse osmosis filtration process is a slow one. That's why you need a water tank, to accumulate water using RO filter.


 Do you need a tank for reverse osmosis?

Small reverse osmosis units need a storage tank because they make water very slowly. Without a tank, a typical under-sink RO unit would put out only a small trickle of water when the thirsty user opened the faucet.

What size RO tank do I need?
In our opinion, even these estimates are a bit high for most customers. Our rule of thumb is to assume about half the manufacturer's stated size. If you need two gallons, get a four-gallon tank. Another point to consider is that you usually don't need as much water as you think you will at one time.

How long do RO tanks last?

If you adjust the air in a tank and do regular maintenance for RO system: 5-10 years. We recommend changing RO tank at least every 5 years

How do I know if my RO tank is bad?

1. Slow, or very little water.

2. It is not possible to adjust air/water pressure in a tank

3. Water smells

4. The age of my tank is more than 5 years.

How do I check my reverse osmosis tank pressure?

How do I increase the pressure in my RO tank?

How to Re-Pressurize Your Tank:

  1. Turn off the feed water supply to the RO.
  2. Drain the old tank completely thru the spigot.
  3. Close the tank's Ball Valve. ...
  4. Disconnect the YELLOW line from the tank valve.
  5. Locate the pressure valve under the blue cap on the tank.
  6. Use an Air Pressure gauge to check the current Air Pressure

Its is easy if you got an air pump with accurate air pressure meter :


Call us, if you need a consultation or new RO Tank:

(929) 357 4522


 PS: Average estimates for new RO Tank installation is only 50$ labor( ClearLifeNY's technician visit)+ 50$ (for parts: RO Tank), so total only 100$.

(Brooklyn, Queens) For other locations, the price can be different.