Why Does My Reverse Osmosis Water Have Bubbles? (+ Fixes!)
Written by: Gene Fitzgerald // Last Updated: Jun 2, 2023
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Water filtered through a reverse osmosis system should normally not have any bubbles and be crystal clear.
You can watch out for bubbles as a sign of potential problems, but you should keep in mind that they could appear under perfectly normal circumstances.
Here’s what you need to know about the presence of bubbles in your reverse osmosis water.
Contents
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Key Takeaways
Here are all the possible reasons that might cause your reverse osmosis water to have bubbles and how to fix them:
- New system or recent maintenance – wait for bubbles to subside
- Air pocket – release
- Air in the source water
- Worn-out RO membrane – replace
- Feed water pressure too high – reduce
- Error during installation or maintenance – fix
- Leakage – fix
How to Check If You Really Have Air Bubbles
You should know how to check if you really have air bubbles in your RO water in the first place. It’s possible that you’re just dealing with some dirt or other contamination making your water cloudy.
If you see large water bubbles getting broken down into smaller ones as they float to the surface before they dissipate, this is completely harmless, and many people would agree that some extra oxygen in drinking water can improve its taste.
A simple test you can perform at home is to fill a cup of reverse osmosis water and leave it idle for a few hours. If, after some time, it has cleared up completely and there is no residue inside the cup, then you’re likely just dealing with air bubbles. Make sure to run your finger around the edge of the cup to check for contaminants. At this stage, water should be crystal clear with no extra smell or taste.
Why Does My Reverse Osmosis Water Have Bubbles?
So, why does your reverse osmosis water have bubbles?
There are several factors that can cause bubbling in reverse osmosis water. Some amount of bubbles is to be expected if your system is brand new, so you should keep that in mind if you have just installed it recently. There could be some other issues involved though.
Newly Installed System or Recent Maintenance
If you recently installed your system, it’s completely normal to expect to see some amount of bubbling when you dispense water into a glass. This also includes cases where you have recently performed maintenance on the system. This usually leaves a lot of accumulated air within the system, which can take some time to remove. How long that can take exactly depends on various factors, including your level of water pressure, the quality of your water, as well as how often you use the system.
New Carbon Filter
Carbon used for filtering water is highly porous and it can release lots of air once it’s been soaked in water for the first time. If you recently installed a new carbon filter, that’s possibly the reason for seeing bubbles in your water. Once again, this is an issue that should resolve itself over time.
New RO Membrane
Reverse osmosis membranes are typically coated with a preservative before they are installed. This can cause some bubbling in the water once the membrane has been put into the system. Just give it some time and see if the bubbles go away on their own.
Air Pocket
It’s possible that you simply have an air pocket trapped somewhere in your plumbing or within the reverse osmosis system itself. In this case the problem should resolve itself after some time. If it doesn’t, you might need to get professional help. One additional indicator of an air pocket trapped in your pipes is a constant sound of knocking or banging.
Air in the Source Water
It’s not unlikely that you might have air in your source water itself. Air passes through the membrane of a reverse osmosis filter quite freely and will make its way to the filtered water supply. Whether that’s the case for you depends on where you’re getting your water from. Keep in mind that city water usually always has some amount of air trapped in the pipes, for example due to nearby constructions sites.
Worn-Out RO Membrane
Air bubbles in your reverse osmosis water could be a sign that you need to replace your membrane. If you have ruled out all of the above courses, you should definitely check if it’s time for a membrane replacement. Don’t just trust the calendar. Sometimes the membrane might get clogged much faster due to circumstances that are beyond your control.
Feed Water Pressure Too High
Reverse osmosis systems need a high level of pressure to operate correctly. However, pressure can be too high in some cases, which can lead to bubbling at the point of instantaneous change.
Incorrectly Installed or Maintained Reverse Osmosis System
If your system hasn’t been installed or maintained correctly, this could also lead to bubbling in some places, especially if air pockets are created. Improper installation can also lead to leaks, which can cause bubbling themselves.
Check for Leaks
That leads us to the final potential cause for bubbles in your reverse osmosis water, which is a leak along your plumbing. A leak may not always cause bubbling, but if a lot of air starts to enter your water as a result of the leak, it could happen.
Further Reading:
How Can I Fix RO Water That Has Bubbles?
Once you have identified the cause for bubbling, you should take appropriate measures to resolve the issue and prevent it from happening again. The fix will depend entirely on the exact nature of the problem – here are some suggestions for what you can do.
Drain 1-3 Storage Tanks
If you’ve recently installed a new reverse osmosis system or maintained and existing unit and want to purge the air from it as quickly as possible, you can drain some extra tanks after you’re done with the normal flushing procedure.
Keep the system running for several hours until the tank is completely full, and then open the RO faucet to let water drain out. Repeat this process multiple times until air bubbles have completely disappeared.
Replace Membrane
If the problem is due to an old membrane, the obvious solution is to replace it. If you did not expect to have to replace your membrane this soon, take note of the date.
There might be certain changes in your water supply that you’re not aware of, which could require you to shorten the delay between replacing your membrane in the future. You should start keeping track of the exact times you’re replacing the membrane as soon as possible in this case, so that you can develop a more sensible schedule.
Reduce Feed Water Pressure
If your feed water pressure is too high, you should simply reduce it. Of course, this can lead to other problems if the pressure drops down too much. Do this gradually and experiment with different pressure levels until you’ve found the sweet spot.
Fix the Leak
If you have identified a leak in your plumbing, you should fix it as soon as possible. Even if it’s not the main cause for the bubbles in your reverse osmosis water, it can still cause other problems such as reducing the overall effectiveness of the filter system and impacting your plumbing in other ways.
Is It Safe to Drink Reverse Osmosis Water with Bubbles?
As you can see above, almost all of the potential causes for bubbles in your reverse osmosis water are actually not harmful. That said, you should not drink reverse osmosis water that has bubbles in it unless you know it’s only air. Ideally, you always resolve the underlying issue first before drinking reverse osmosis water.
If you have any questions about bubbles in RO water please don’t hesitate to leave a comment below!
About the Author Gene Fitzgerald
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