How Long Do RO Tanks Last? + When to Replace Them
Written by: Gene Fitzgerald // Last Updated: Mar 6, 2023
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Reverse osmosis tanks store filtered water and supply it to the faucet whenever you need it.
They are relatively simple structures, but they’re not immune to wear and tear.
So how long do RO tanks last? And when should you replace them? This article has all the answers!
Contents
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Key Takeaways
RO tanks last 3-10 years, depending on how well you maintain them. You should replace your RO tank if:
- It is leaking.
- There’s low water flow from the RO faucet although the tank is full and even after repressurizing it.
- The filtered water has a foul odor or taste and tank sanitization didn’t help.
- The tank bladder is clearly damaged.
- The tank loses pressure a short time after you repressurize it.
Lifespan: How Long Do RO Tanks Last?
So, how long do RO tanks last?
Some experts say RO tanks last 7-10 years, while others believe they only last 3-5 years.
Truth is, your RO tank’s lifespan largely depends on how well you maintain it. With proper maintenance and care, your tank will serve you a good number of years (anywhere from 3 to 10).
The quality of the filtered water also affects how long a reverse osmosis storage tank lasts, among other things. Filtered RO water is acidic and can corrode the plastic bladder in the tank. So the more acidic the filtered water, the more the corrosion, and the shorter the tank’s lifespan.
Note: Obviously, the tank’s overall quality also affects its lifespan. A cheap, low-quality tank will not last as long as a high-quality one. So when shopping for a new reverse osmosis tank or system, don’t set your budget too low.
Does Metal Last Longer Than Plastic?
No, a metal tank does not necessarily last longer than a plastic one. The RO tank’s outer shell does not affect its lifespan—what matters is the bladder inside the tank.
In both metal and plastic tanks, the bladder is made of rubber. So under similar conditions, a metal and plastic RO tank will last the same number of years.
The main advantage plastic tanks have over metal ones is that they do not rust, so they maintain their appearance.
Can a Reverse Osmosis Tank Really Go Bad?
Yes, a reverse osmosis tank can and will go bad.
The bladder inside the tank expands and contracts as water flows in and out, which causes gradual wear and tear eventually resulting in a rupture.
Another way an RO tank could go bad is if the seal between the bladder and the tank fails. This isn’t very common, but you must replace your tank if it happens.
These scenarios above are only two ways your tank could go bad – the point is that it happens.
Tell-Tale Signs That an RO Pressure Tank Needs Replacing
There are unmistakable signs that it’s time to replace your RO pressure tank. Let’s see some of them.
Low or No Water (Ruptured Bladder)
If your water stops running a few seconds after you turn on the RO faucet, it could mean that the tank can’t force the water out through the faucet due to low pressure. The bladder is likely ruptured and the only solution is to replace the tank.
Bad Water Taste or Odor
RO tanks store purified water for later use. But over time, contaminants build up in the tank, resulting in unpleasant tastes and smells.
If you notice this happening, sanitize your tank immediately. If that doesn’t solve the issue, replace your tank quickly to stop the contaminants from further ruining your drinking water.
Leaks and Drips
If you notice leaks or drips around the RO tank and its fittings or valves, it’s definitely time to replace it – unless there was a lose connection.
Repressurizing Your Tank Could Be the Solution
Fortunately, you don’t always have to replace your tank whenever you notice something wrong. Repressurizing your tank could be the solution in cases where the tank’s pressure is too low.
Empty RO storage tanks should have a pressure of 6-8 psi.
You can check your tank’s pressure with a pressure gauge. If the pressure is too low, pump some air into the Schrader valve until you reach 6-8 psi (you can use a bicycle pump for this). Ensure you only add a small amount of air at a time to avoid increasing the pressure too much and rupturing the air bladder.
Note: Replace your tank if it loses pressure a few days/hours after you repressurize it.
What to Do and What to Avoid to Make Your Reverse Osmosis Tank Last Longer
We’ve compiled quick tips showing what to do and what to avoid to make your RO tank last longer!
Do: Place Your RO Tank Upright
RO tanks are supposed to be placed upright, but they’re sometimes placed on their sides due to space constraints.
RO tanks work perfectly fine when placed on their side, but unfortunately, the water presses the bladder down on one side and wears it out. The constant strain from being in the side position eventually causes a hole to form in the bladder. Keep your tank upright to save yourself the trouble.
Do: Use Regularly
Using the RO system regularly is another way to keep the tank in top shape. Regular use “exercises” the bladder, keeps the water fresh and prevents it from accumulating biofilm in the tank.
Do: Sanitize
Sanitizing your RO tank keeps out biofilm and preserves the quality of your water. This helps your RO tank last longer.
Avoid: Dispense Too Much Water At Once
Using your RO system regularly is advisable, but know where to draw the line. Dispensing too much water at once can cause the bladder to contract and move about excessively.
This extra movement eventually causes the bladder to rub against the walls of the storage tank. Although the tank’s walls are smooth, prolonged rubbing of the bladder against them will make it more likely for the bladder to develop cracks and holes.
Avoid: Chlorine
Chlorine and RO tanks don’t go well together. This is because chlorine can make the tank’s bladder brittle. Municipal water usually contains chlorine since it’s pre-treated. This means that your RO system is constantly filtering chlorine.
Reverse osmosis systems typically include a carbon pre-filter that filters out the chlorine. But the filter gets worn out after a while and no longer works.
If the chlorine goes through the system unfiltered and gets into the storage tank, it can damage the bladder and cause it to crack. So you must ensure that your RO system removes most chlorine before the water enters the tank.
Avoid: Acidic Water
RO water tends to be slightly acidic. That’s fine as long as water pH doesn’t drop too low. Why? Acidic water is more corrosive and will attack the plastic bladder inside your RO tank.
Avoid: Under-Pressurized Air Bladder
An under-pressurized air bladder is another thing to avoid if you want your reverse osmosis tank to last long.
When the pressure in the air bladder is too low, it allows more RO water to flow into the tank. The extra water causes the bladder to stretch excessively. If this continues for a long time, the overstretched bladder wears out faster than usual and might even rupture.
Check your RO tank’s air pressure whenever you’re about to change the filters in the system. You can check the air pressure using a low-pressure gauge. The standard range of pressure for RO tanks is 6-8 psi. So the pressure must be within that range.
Further Reading:
What Is a Reverse Osmosis Tank, and How Does It Work?
A reverse osmosis tank is a storage tank that collects RO water after filtration. A storage tank is necessary because reverse osmosis is a slow process (it literally purifies water one drop at a time). Storing water in a tank ensures that there’s always water available whenever you turn on your reverse osmosis dispenser.
RO tanks are hydropneumatic, meaning they hold both water and pressurized air. The tank contains an air chamber and a water chamber divided by a rubber bladder. As the RO system fills purified water into its tank, the weight of the water compresses the air chamber, increasing the pressure. When you open the faucet, the built-up pressure shoots the water out of the tank.
Thanks to the air chamber within the tank, RO storage tanks do not need a booster or delivery pump to work.
How Much Does a New RO Tank Cost and Where to Get One?
The price of your RO tank will depend on its size, brand, and quality.
Generally, a reasonable starting price for an RO tank is $40-50. However, higher-end tanks can cost $150 and more.
You can get RO tanks from a local water treatment expert or hardware store. You could also get it online from a brand or a large retailer. If you’re shopping online, do your due diligence and ensure you’re buying from a reputable source.
If you have any questions about when to replace a reverse osmosis tank please don’t hesitate to leave a comment below!
About the Author Gene Fitzgerald
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