If you have had a reverse osmosis system for a while, you probably know that your reverse osmosis water is stored in a pressurized tank to provide you with reverse osmosis filtered water whenever you need it. But, you notice that you are not getting as much water from your tank as you used too.
Can A Reverse Osmosis Tank Go Bad? An air-charged reverse osmosis storage tank needs replacement when the water bladder develops a leak, or the valve seal fails. A water-on-water storage tank may also need replacement when the valves in the control head fail. Replacing a reverse osmosis storage tank is quite simple, and inexpensive.
Of course, no one wants to find that the water storage tank for their reverse osmosis system has gone bad, but when it does, it is very simple to replace, and you might even want to upgrade to a larger tank while you are at it.
Let’s find out if your reverse osmosis storage tank has gone bad, and show you how easy it is to replace it.
How does a reverse osmosis storage tank work, and how can it go bad?
A standard air charged water storage tank is simply a tank that contains a bladder to hold your reverse osmosis filtered water in, and store it for when it is needed.
In order for you to get the water out of the tank, it needs to be forced out by air pressure pressing against the outside of the water bladder.
In the cases of a standard reverse osmosis storage tank, this means that there is a water bladder inside of the tank that is suspended from the top where it feeds water in and out of the tank. (Source)
The bottom of the tank is full of compressed air that presses against the outside of the water bladder to force the water out to the reverse osmosis faucet.
A water-on-water reverse osmosis water storage tank works very much the same way, but instead of pressurized air forcing the water out of the tank, household water is feed into the tank to compress the water bladder and force the reverse osmosis water out of the tank.
That sounds very simple, what could make the storage tank go bad?
Even though a reverse osmosis water storage tank is a very simple device, it still has a bladder that expands and contracts. This is a moving part, and like any moving part, it will wear out eventually.
Signs that your reverse osmosis storage tank needs replacing.
The most common sign that your reverse osmosis storage tank is no longer functioning properly is that you get almost no water from it.
If you turn on your reverse osmosis faucet and the water stops after just a few seconds, your reverse osmosis system is not producing water, your storage tank is not allowing water into the tank, or it is not able to force the water out of the tank.
The problem may just be that your storage tank needs to be re-pressurized.
See my article on How To Re-pressurize A Reverse Osmosis Storage Tank, follow the instructions to see if your tank just needs to be re-pressurized, if your reverse osmosis is still not producing, check for these indications that your reverse osmosis tank has gone bad.
Check to see if your tank is full, and I mean FULL! What I mean by this is, when a reverse osmosis tank is full under normal conditions, there is still a portion of the tank that has pressurized air in it.
Shake your storage tank. If it feels like it has lots of water in it, but it is not full from top to bottom, it may be fine.
But if you give your storage tank a shake, and find that it seems to be completely filled with water, the bladder may have developed a leak and filled the entire tank, which means that the tank needs to be replaced.
Before replacing your tank, I recommend trying to repressurize it, just to make sure that it needs to be replaced.
Check out my article How To Re-pressurize A Reverse Osmosis Storage Tank first, and if you determine that the tank needs to be replaced, check out my recommended reverse osmosis storage tanks to find the best replacement tank for your needs.
A storage tank can just go bad from simple wear and tear.
Fortunately, reverse osmosis water storage tanks are made very sturdy, and the bladders that hold the filtered water are very strong and flexible.
But each time you draw a glass of reverse osmosis water from the storage tank, the bladder contracts, and every time your reverse osmosis system makes more filtered water and puts it in the tank, the bladder expands.
Just think about this happening several times every day for many years.
Even though the rubber bladder is very strong, it can only take so much stretching and contracting before the rubber develops a crack or hole in it.
This usually takes many years before the bladder develops a leak. I have seen some reverse osmosis storage tanks that were 15 years old and still working just fine, but that is not always the case.
Just like a tire on a car or truck, eventually, the rubber bladder wears out and has to be replaced.
Reverse osmosis tanks that lay on their sides may wear the bladder more on one side.
Sometimes, when space is an issue, the water storage tank for a reverse osmosis system may be placed on its side, rather than standing up.
Although the tank will operate perfectly fine in this position, the water in the bladder will press the bladder down on one side and can cause the bladder to wear more on the side that faces down.
Because the side of the bladder that faces down may have much more wear and tear than the top facing side, the bladder can develop a hole due to the extra wear on the one side.
The bladder may rub on the inside of the tank.
When large amounts of water are drawn from a reverse osmosis storage tank, the bladder contracts a great deal and that means that it moves quite a bit.
This movement causes the bladder to rub against the inside walls of the storage tank.
Although the walls of the tank are smooth, the continuous rubbing caused by emptying and re-fill the tank will create thin areas on the rubber bladder that make it more likely to develop a hole or crack.
The seal between the bladder and the tank may fail.
The bladder of a reverse osmosis storage tank is tightly sealed to the valve that allows the water to enter and leave the tank, but this seal can fail due to manufacturing flaws or wear and tear.
It is not very common that I find the seal of a storage tank valve failed, but it has happened and the storage tank will need to be replaced.
Chlorine can make the storage tank bladder brittle and crack.
Municipal water is often chlorinated to make it safe for drinking.
A properly functioning reverse osmosis system with a Carbon pre-filter will remove the chlorine for a period of time, but eventually, the carbon can no longer remove any more chlorine, and it can end up getting into the storage tank of your reverse osmosis system.
If chlorinated water gets into the bladder of your reverse osmosis storage tank, the chlorine will cause the rubber to deteriorate and become more fragile. Eventually, the bladder becomes so fragile that it will crack and no longer be able to hold your filtered water.
The bladder could rupture from the air pressure being too low.
When your reverse osmosis system produces filtered water and feeds it into the systems storage tank, it will continue to feed the water until the pressure from the storage tank tells it to stop.
If the air pressure in the storage tank is low, the bladder will get overfilled with reverse osmosis water, causing it to stretch more than it is supposed to.
If the air pressure remains low for a long period of time, the bladder will continue to stretch making it wear quicker than normal.
In some cases, I have seen a reverse osmosis bladder that has stretched to the point where it was near twice the original size before developing a hole.
It is important to check your reverse osmosis storage tank air pressure with a low-pressure gage whenever you change the filters on your system.
Most standard tanks will work best at 7-8 pounds per square inch of pressure.
Some water charged reverse osmosis storage tanks have valves that may stick.
Reverse osmosis water storage tanks that use your household water pressure to force the reverse osmosis water out of your storage tank have been around for quite a while, and some of them work for many years without a hitch.
But in some water charged storage tanks, there are valves that control the flow of the water going in and out of the tank. After a while, these valves tend to stick and no longer allow the water to come out of the tank.
I have cleaned and lubed these valves with some success, but I have found that converting to a standard reverse osmosis tank has always been the better solution to this problem.
Can you change the bladder in a reverse osmosis storage tank?
Most reverse osmosis storage tanks are sealed and not designed to have the bladder replaced. But there are some water storage tanks that have a screw-off top where you can access the bladder and replace it.
The main problem that I have found with this type of storage tank is that the seal between the tank and the screw off cap allows the pressurized air in the tank to slowly escape.
If you don’t mind repressurizing your tank regularly, this might be ok, but I find that most people prefer a reverse osmosis storage tank that will hold the air pressure better.
What can I do to make my reverse osmosis tank last longer?
For the most part, there isn’t much that can be done to make a reverse osmosis storage tank last longer. But to ensure that you get full use out of your storage tank, it is a good idea to let the bladder inside of your tank empty completely once in a while.
I find that emptying your reverse osmosis storage tank once a month is a good idea, for a few reasons.
Keeping your water fresh:
Because a reverse osmosis system replenishes water that has been used from the storage tank regularly, the new water gets mixed with older water.
Although this does not make the water bad, completely emptying your reverse osmosis storage tank and replacing it with fresh water ensures that the water that you are drinking has not been sitting around for a long period of time.
Keeping the water bladder limber:
By emptying the bladder out completely, you are allowing the rubber to constrict and flex, this will help the bladder to continue to expand and contract as it gets older and make it less likely to crack.
Which is better, a plastic or metal storage tank?
For the most part, I don’t think that it really matters if you use a metal tank or a plastic one. What really matters is the water bladder inside of the tank, and that the tank holds air pressure.
A plastic storage tank is a little bit lighter than a metal one, but this is not really a benefit because you hardly ever need to move your reverse osmosis storage tank.
A metal reverse osmosis storage tank maybe a little more durable, but how durable does a reverse osmosis storage tank really have to be? It will basically be sitting in one spot for many years without being touched by anything!
I recommend choosing a reverse osmosis storage tank based on your water needs. Most reverse osmosis drinking water systems come with a storage tank that will provide approximately 2.5 gallons of ready to use reverse osmosis water.
If you feel that you would like to have more than that available to you, check out my recommended reverse osmosis storage tanks, and find one that will best fit your needs.
How much does a new reverse osmosis storage tank cost?
Most people are surprised to find out how inexpensive it is to replace or upgrade their reverse osmosis storage tank. I have found that to replace the most common 4-gallon size reverse osmosis tank costs about $40 or less.
It seems to average about $10 per 1 gallon of tank size.
In other words, a 4-gallon storage tank is about $40 or less, a 10-gallon storage tank is about $100 or less, and an extra-large 14-gallon reverse osmosis storage tank will be about $140 or less.
Of course, different brands of storage tanks may be at different price points for similar-sized tanks, but I find that the $10 per gallon is a pretty good rule of thumb when looking to purchase a new reverse osmosis storage tank.
Where can I get a new reverse osmosis storage tank?
Because there are many different sizes of reverse osmosis water storage tanks, you aren’t likely to find the best-sized tank for your needs in your local hardware store. That’s why I have selected some of the most popular sizes available that you can purchase for a great price online.
Check out my recommended reverse osmosis storage tanks to find the best-sized storage tank for your needs.
How can I safely dispose of a used reverse osmosis water tank?
Hello P York, and thank you for the question.
A reverse osmosis tank may or may not be recyclable, you would need to contact your local authorities to determine the best way to dispose of it.
I hope this was helpful.
Paul
how do I empty water tank that is full of water, before disposal?
Hello Richard and thank you for the question.
If the tank doesn’t empty by opening the valve on the tank, use a bicycle air pump and add about 15 pumps of air to the tank. This should force the remaining water out of the tank when you open the valve.
I hope this was helpful.
Paul
Hello!
I have reused 2 RO storage tanks.
It is possible to cut or saw the top conus part and clean all the bladder and the inside plastic cover.
Then I made some holes at the sides of the cylinder and sprinkled the ground. Now I have a finik palm. (gardening)
And I made a knight’s helmet for my daughter. (toy)
Thank you.
Our reverse osmosis system was installed 20+ years ago. We’ve never changed the filter or bladder or inspected the tank. Is it possible for the tank to have developed corrosion and release iron into our drinking water? We have always used the system several times per day but seldom empty the tank. I am particularly concerned about iron because both me and my husband have recently discovered extremely high ferritin levels in a thorough lab analysis. Our medical provider is concerned about the cause because we are otherwise healthy people. I appreciate your insight.
Hello Leesa and thank you for the question.
I HIGHLY RECOMMEND that you no longer drink the water that is coming from your reverse osmosis system!
Not only will the old filters and membrane no longer be filtering your water, but it is VERY possible that there are bacteria growing inside of the system and corrosion of internal surfaces.
Most reverse osmosis systems should have their filters changed at least every 2 years at most and the membrane may last as much as about 10 years on some systems at best.
An average reverse osmosis drinking water system will last up to 15 years before it should be replaced. I HIGHLY recommend that you consider a new reverse osmosis drinking water system or at least have the filters and membrane changed by a professional that will also be able to sanitize the system.
I hope this was helpful.
Paul
If I replace the RO tank what do I do with the old one, how do I dispose of it? Does the tank have to be recycled?
Hello Joe and thank you for the question.
Recycling requirements vary depending on your area. Try searching for a “recycling facility near (your area)” and contact them for details.
Hope this helps.
Paul
hello i got a Question my on my ro- system the pressure tank is not holding pressure ? plus i can’t put any air in it could this be faulty valve you think i have to replace the tank any help on this is appreciated
thanks Leo
Hello Leo and thank you for the question.
I believe that the water bladder in your tank has ruptured. When a pressure tank bladder ruptures, it will only produce a small spurt of water and then stop and because the tank does not expand, you will not be able to add more air to the tank.
I am quite sure that it is time to replace the storage tank.
See my Recommended RO Storage Tanks for a replacement.
I hope this helps.
Paul
I drained and re-pressurized my tank to 8PSI. After letting the tank fill again, the pressure rockets up to 30PSI. I let air out back to 8. If a wait a while and open the valve, the water shoots out great for 2 seconds, then dies out (Not completely) if I check the air, it’s at zero PSI. I add more air and the same thing happens.
Basically the PSI reading changes all the time. Is the tank bad?
Hello Jack and thank you for the question.
The air pressure in the tank should be at 8 PSI when the tank is empty and it will be much higher when the tank is full of water.
Empty the tank out again and get the pressure back to 8 PSI (when the tank is empty). If you only get a small amount of water from the system and you are NOT able to get very much water from the tank, the water bladder inside of the tank could have ruptured or torn. But often the bladder inside of a reverse osmosis storage tank will usually last for many years.
Get the air pressure in the tank back to 8 PSI (and make sure that it is at 8 PSI with a low-pressure gauge, a car tire pressure gauge will not give an accurate enough reading).
Let the tank fill and then turn on the faucet to see if the tank empties. If the tank empties, your tank should be fine.
I hope this was helpful.
Paul
Hello. I have an RO system and I’m not getting much water to the tank. I have just replaced the filters and my intake water seams fine. The pressure at the tank is 10-12psi. I suspect the tank is bad because it is kind of rusty on the top. But I’m not sure if the tank is bad why the water is not still going to it.
Thanks Chris.
Hello Chris and thank you for the question.
10 – 12 psi is too high for a standard reverse osmosis storage tank. If the pressure in the tank (When empty) is more than about 8 psi, the air pressure won’t allow water into the tank.
You should use a LOW-PRESSURE tire gauge to make sure that the air pressure is correct.
Empty the tank (completely) and then check out my article “How To REPRESSURIZE A Reverse Osmosis Storage Tank” for detailed steps on getting the air pressure correct in your storage tank.
I don’t think that the tank is bad just because it has a little rust on it, but if you find that you can’t get it working, you might want to check out my recommended reverse osmosis storage tanks.
I hope this was helpful.
Paul
How long can my RO system sit without being used?
If we are gone for a month or 2 do I need to replace the filters and sanitize the system before using it again?
Or just flush the tank out?
Also, what’s the pro’s and con’s of having a soft water system?
Thank you,
Jeff
Hello Jeff and thank you for the question.
Providing that there is no air inside of the system, there should be no bacteria growth inside of the system after 2 months of sitting unused.
I recommend that you flush out the tank a few times before drinking from the system and using a reverse osmosis sanitizer would be a good idea to play it safe.
If you have someone watching your home for you while you are gone, have them turn on the reverse osmosis faucet once a week when they arrive and let the tank empty, then shut off the faucet to let the system refill to keep the water fresh.
There should be no need to change the filters as the water inside the system should not cause them to clog or damage.
There are many pros and cons to a water softener, but the most crucial pro, if you have a reverse osmosis system, is that hard water can damage the reverse osmosis membrane of the system. Hard water can also build up inside of hot water systems, corrode faucets, and appliances, cause dry skin and hair, and permanent etching on your glassware and dishes.
I hope this was helpful.
Paul
Is it ok to use ro system without a tank?
Hello Noy and thank you for the question.
On a standard reverse osmosis system, the water that is stored in the storage tank has already been through the reverse osmosis membrane and all of the filters except possibly for a final polishing carbon filter so removing the storage tank from the equation should still provide you with filtered water.
The only disadvantage of not having a storage tank would be that a standard reverse osmosis system makes filtered water very slowly. Without a storage tank to hold a supply of pressurized filtered water, you will just get a very slow trickle of water.
It could take several minutes just to fill an 8-ounce glass with reverse osmosis water.
Also, the lack of back pressure provided by a full water storage tank could affect the quality of the water coming from the membrane.
If you are concerned that your reverse osmosis tank is no longer working correctly, check out my article on How To Pressurize A Reverse Osmosis Storage Tank.
I hope this was helpful.
Paul
Thank you very much, very helpful information.