How Often Should You Change Your Reverse Osmosis Tank?

As an Amazon associate We earn from qualifying purchases, at no additional cost to you.

If you have a tanked reverse osmosis system, you might be wondering whether the tank requires replacement. The answer is yes!

A storage tank plays a significant role in an RO system. It stores the purified RO water awaiting use. And in case of emergencies (like water shortage), the stored water comes in handy.

However, this storage tank requires replacement after several months/years of use for optimal performance.

But how often should you change your reverse osmosis tank? If you live in an area with very hard water, you need to replace the tank every 6 to 12 months.

On the other hand, if living in an area with soft water, change the tank every 3 to 4 years or when it stops operating as intended.

What is a Reverse Osmosis Tank?

How Often Should You Change Your Reverse Osmosis Tank

An RO tank is a hydropneumatic tank designed to sit under a sink in line with your RO system. The storage tank collects the water gradually purified by the RO membrane.

And since the reverse osmosis filtration process is slow, water is pushed through the membrane drop after drop.

The tank lets the water accumulate so that when you want to pour yourself a glass of water, you get it immediately.

Reverse osmosis tanks are usually made from rolled steel and lined in the interior with an inert butyl material. The butyl lining prevents your water from coming into contact with steel.

How Long Should a Reverse Osmosis Tank Last?

A well-maintained RO tank should last 5 to 7 years on average. This, however, changes with the frequency of use. For instance, if you use your RO system every day, expect to replace the tank in 3 years.

You don’t need to change the tank until the air bladder goes bad or is unable to push the water out of the tank. Replace the tank if you notice that the membrane is deteriorating faster.

When this happens, you’ll get approximately one glass of water at standard pressure. When the pressure drops, you’ll get a tiny stream of water, even if the tank is full of water.

This means that you need to replace the tank.

Why Does a Reverse Osmosis Tank Lose Pressure?

Over time, air can seep out of the tank, making it lose pressure charge. This results in a decrease in your water’s flow rate.

If you stop receiving water at the faucet and think that your tank has lost pressure, it’s advisable to conduct a troubleshooting test.

To do so, isolate the tank and run the system to ensure that it can still produce water. Next, lift the tank to test its weight.

If the storage tank is heavy and filled with water, and the system can still filter water when separated from the tank, the tank has lost air charge.

When Should You Replace Your Reverse Osmosis Tank?

If you notice that only a stream of water comes out of the faucet, even if the tank is heavy and full of water, it’s an indication that you need to replace the tank.

If the water comes out of the air valve when you test the air pressure, the bladder in the tank has failed. And since it’s not a fixable problem, you’ll have to replace the storage tank.

How to Replace a Reverse Osmosis Tank

How to Replace a Reverse Osmosis Tank

To install a new RO tank, you have to remove the old one from the system first. It’s a very easy process, which you can complete within a few minutes.

So, how do you remove the old RO tank?

  • Shut off the flow of water to the tank.
  • Shut off the water going to the reverse osmosis system.
  • Open the faucet to release the air pressure.
  • Place a towel under the tank to prevent the mess from the water that might spill in the process.
  • Disconnect your tank from the tubing.

To install the new your new reverse osmosis tank:

  • Wrap Teflon tape around the threads in about 3 turns.
  • Screw on the tank’s shut off valve.
  • Push the tubing into your tank’s shut off valve and then pull back to ensure that it’s tight.
  • Turn on the water to the RO system and monitor it for a few hours to ensure no leaks as the RO tank fills with water and air pressure increases.

How Much Will It Cost You to Replace an RO Tank?

If you are going to replace your reverse osmosis tank, be ready to part with anything from $400 to $1000. It can be expensive depending on the model, capacity and whether you’ll be hiring a professional to do the replacement for you.

Is It Necessary to Sanitize a Reverse Osmosis Tank?

It is necessary to sanitize your RO tank as it may contain bacteria and other organisms that can affect the taste and smell of your water. Worse still, it can negatively affect your health.

Ensure that you sanitize the tank once every year. In fact, since you have to change some of the filters annually, pair this maintenance task with filter change.


Generally speaking, RO tanks last quite a long time. Most are usually warrantied for 5 years but tend to operate beyond that.

However, should your stop getting water on your faucet even when your tank is full, check to ensure whether the bladder within the tank has failed. After confirming that it has indeed failed, it’s time to get a new RO tank since the problem is not repairable.

Leave a Comment