Air in Pool Pump: How to Prevent Bubbles (Ultimate Pool Owner’s Guide)

An air in pool pump will ensure that the suction side of the pump is free of air. It can help to prevent pool pump bubbles. Read more here.

Excess air in pool pump and filter is more than just an annoyance; it may be a sign of a problem – one that may or may not require a small or major solution. However, if left untreated, it will inevitably lead to other issues, which might have a minor or major impact on your pool maintenance.

This article dives into what causes air bubbles and how to prevent them in a swimming pool. 

What Can Be the Source of Bubbles? Why Not Consider Air in Pool Pump

Air Bubbles in Pool

Remember that even when a pool’s filtration system is operating well, it will occasionally produce a few bubbles from the return jet, particularly during the initial start-up of the pump. Air bubbles are not a cause for alarm if they only occur shortly after starting the pump and vanish after a minute or two. 

Moreover, nine out of ten times, air bubbles in the pool are not an underground pool issue. More often than not, it is faulty aboveground equipment that causes it.

Here are some of the major problems why you experience air bubbles in the pool:

  • The pool’s water level is too low.
  • The strainer pot lid is not securely fastened, or the O-ring is missing or loose
  • The pump and valves are not tight enough.

The good news is that changing an O-ring is a simple do-it-yourself project that costs less than 50USD!

Is Your Pool Water Level in the Optimal Range?

Clear Water in Pool with Blue Tiles

One of the most common causes of air bubbles in the pool is that the water level is too low. 

If the water in your pool is below the optimal range, the skimmer may suck in air and blow it through the pump/filter system.

If this is indeed your case, it’s necessary to add water. We recommend that the water level in the skimmer be maintained halfway to three-quarters way up the skimmer.

Tip: Never drain a fiberglass pool unless necessary. You risk voiding your warranty and perhaps causing harm to the pool.

Is Your Strainer Lid Tightly Sealed?

Hand Holding Rubber O-ring

The strainer pot lid is there to keep all the debris in its right place, not to mention that it also keeps water from leaking when you are not using your pool. The lid has a rubber O-ring seal on top of the handle to ensure water does not leak out when draining the pool. 

A damaged O-ring will cause your pool to lose water and air bubbles to occur. If you suspect this is your problem, replace it with a new one that came with your pump equipment or buy one online or at your local hardware store.

Here’s how to check the O-ring beneath the lid:

  • Turn off the pool pump
  • Take off the lid
  • Inspect the o-ring
  • Make sure it’s in good condition and tightly secured
  • Remove any grit or debris that may obstruct the lid from being tightly secured.

Is there anything missing or loose? Check for any loose pieces on the pool’s equipment. Replace any missing O-Ring if necessary.

Is Your Pump/Valve Securely Tightened?

Water Valve and Pipe in Swimming Pool

You should make sure to tightly secure the fitting(union) between the pool pump and valves.

If there’s an o-ring in the strainer pot lid, surprise! There’s also an O-ring here too.

Here’s how you can check the O-ring between the pool pump and valves:

  • Turn off the pool pump
  • Remove the nut in the union
  • Check to see that the O-ring is there and in excellent condition.
  • Examine the union to ensure no grit or dirt is preventing it from tightly closing.

Often, when you’re putting back the pump/filter together, the O-ring fittings can slide or fall out, which leads to bad things – like letting air in. Ugh. Don’t let that happen to you!

If Bubbles Are Still Occurring, Consider Adding Air in Pool Pump

If you check all three of these items and still have air bubbles, you may have a more serious issue—such as a suction-side leak in your plumbing, which would come in either your main drain or your skimmer line.

That’s a lot for most pool owners to manage on their own, so contact your friendly local pool pros. They’ll be delighted to help!

How to Prevent Future Air Bubbles in the Pool

It’s always better to prevent than cure. So here are some reasonable tips to help you avoid air bubbles in your pool:

Know the Warning Signs

Knowing the warning signs is the best way to tell if there’s a problem with your pool’s above-ground equipment. If you’re noticing air bubbles in your pool, it’s time to act.

Check Pool Equipment Regularly

Make sure all the pool equipment is in good working condition. Here are some signs that your pumps and filters may need immediate repair or replacement:

  • The pool pump and filter stop working. 
  • The pool pump and filter cycle on and off frequently, but your pool’s water level is not increasing.
  • The main drain is clogged.
  • The skimmer return line has an obstruction such as a tree limb or rotted surface material. 

Clean Filter Regularly

Make sure to clean the filter media regularly, at least once every month or two weeks during the swimming season.

Check Air Bubbles in Pool

If you notice frequent air bubbles in the pool, you should also consider testing your water for pool chemicals, pH level, and total alkalinity.

Water chemistry issues can prevent the filter from removing those tiny particles that make up those pesky air bubbles. So monitor those levels and test them regularly to ensure your pool is as clean and clear as you want it to be.


When it comes to pool pumps and filters, the air in the system is not a good thing. Excess air in the pool pump and filter is more than just an annoyance; it may be a sign of a problem – one that may or may not require a small or major solution.

However, if left untreated, it will inevitably lead to other issues, which might have a minor or major impact on your pool maintenance.

Check out our website for great pool articles. Maintaining your swimming pool is easier than you might think. Below are a few helpful pool guides.

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About the author

Brian Anderson

The rather dry pool world out there is in need of some passion to make it shine. With the help of my son Ruben and his wife Maria our mission is to help you create the favorite spot of your house - your pool.

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