How to Get Rid of Pool Foam

Pool Care Chapters

How you can get rid of pool foam will depend on what is causing the pool foam. Here’s the quick answer to your question. We recommend sticking around for the long answer because the additional information gives context and in-depth answers that you will likely find to be useful.

Potential Cause #1: Body and Hair Care Products

Solution: Pool Shock (Chlorinated shock for best results)

Potential Cause #2: Low Calcium Levels

Solution: Balance the chemicals to these specifications:

  •  pH: 7.5 PPM 
  • Calcium
    • Fiberglass and Vinyl: 175 to 225 PPM
    • Concrete and Plaster: 200 to 275 PPM
  • Chlorine: 1 to 3 PPM

Potential Cause #3: Too Much Algaecide

Solution: Time. This one solves itself.

Defoamer – Temporary Solution to Remove Foam Quickly

This solution will not address the underlying issues. However, if you have some friends coming over and you don’t want it to look like a bunch of pee foam is floating in your pool, this quick fix might be just what you need.

Can clear the pool up in about 30 minutes.

Doesn’t mess with the water chemistry

The main active ingredient is silicone.

Long Answer

Pool foam forms when a chemical is introduced into the pool. The source of the chemicals will often be a plant, an animal, or human byproducts, but it can also be affected by chemical and environmental factors. The discovered source of the pool foam will determine the solution that will need to be applied.

Potential Cause #1
High Organic Load – Hair, Body, and Clothing Byproducts 

Think of all the products that are applied to the human body. Shampoos, conditioners, hair gels, hair sprays, hair mousse, lotions, make-up, perfume, cologne, and deodorant all enter the pool with the swimmers and a lot of these products are left behind.

In addition, insects, animals, and even plant debris can contribute to this organic load. Body waste products also add to this chemical stew. The urine, poop, and pee that occasionally break into the pool can quickly turn swimmers’ stomachs and destabilize the pool’s chemical balance.

It makes the water thick with a high organic load which is disgusting. That organic load blends into a biological soup agitated into foam by the wind and pool pump. Breaking all of this biological material down will require a significant amount of sanitizer.

Shock Your Pool

Shocking your pool with chlorine shock will quickly attach to almost anything contaminating the pool. Chlorine shock destroys the chemical bonds and proteins that might be polluting your pool and causing those nasty clumps of pool foam.

If you are hesitant to use chlorine, you can still use a non-chlorinated shock. However, expect reduced results. The chlorine that is likely making you uncomfortable is also what makes it effective. 

Potential Cause #2
Low Calcium Levels

The term, water hardness, primarily describes how many molecules of calcium and magnesium are in the pool relative to the molecules of water. To maintain a healthy pool, these minerals need to be properly proportioned to the water content. When these proportions are out of balance, we start running into issues. We can measure the proportions in parts per million (PPM).

Hard water means that there is a lot of mineral content, primarily in the form of magnesium and calcium. Soft water means that mineral content is low. 

When the water is too hard (too many minerals), you’ll start having calcium scaling issues. If it’s too soft (too few minerals), your pool might start to have foaming issues, and the sanitizer becomes ineffective. Pool owners use calcium as a dial to control the balance between hardness and softness.

While low calcium (Soft water) levels can certainly be a factor that allows for foaming, low calcium is rarely the sole culprit to a foam-ridden pool. Usually, foam forms when calcium is low and the organic load is a bit high. This happens because low calcium levels reduce the water’s surface tension which makes it easier for foam to form.

Surface tension is a byproduct of water molecules’ natural attraction to other water molecules. When that attraction is strong, it is more difficult for the foam to form. 

Adding calcium to the water increases this surface tension. If the foam is forming in your pool, we likely need to increase that surface tension till the water is no longer considered soft.

However, before we get into that, we want to point out some small classification differences between tap water and pool water. 

What is classified as hard water and soft water changes from tap to pool, and their contrasting classifications might be confusing if you come across one set of classifications and not the other.

Tap Water Classifications

  • Soft Water: 10 to 50 PPM
  • Hard Water: 100 to 200 PPM
  • Very Hard Water: 200+ PPM

Pool Water Classifications

  • Soft: 100 PPM
  • Hard: 300+ PPM

Increase the Calcium Levels

The ideal calcium PPM levels change depending on who you ask. It is difficult to say who is definitively right since chemistry is affected by environmental factors and ideal PPM requirements change with pool types. 

There might be a study out there somewhere that can give an objective answer. However, until we find that study, we will just give you the results of our research. These appear to be the ideal PPM levels for each pool type:

  • Vinyl: 175 – 225 PPM
  • Concrete and Plaster: 200 to 275 PPM

Potential Cause #3

If you are asking, “Does algaecide cause pool foam?”,  Have you recently added algaecide to your pool? If so, that’s probably what is causing it. There are a couple of ways that algaecide can cause your pool to become foamy. You can either use too much product or a low-quality product.

Too Much

When we say, “too much,” we aren’t necessarily saying that you haven’t followed the algaecide’s instructions. You can follow them perfectly and still develop pool foam. 

This happens because algaecide needs algae to attack. If it hangs around being unattached, the free-floating algaecide is eventually agitated into foam by the pool pump.

Low-quality Algaecide

As a rule, you should avoid 10% polymer and copper-based algaecide. These low-quality products will attack the algae. However, they also come with potential side effects such as staining pool surfaces and causing pool foam.

Time. This one solves itself.

Algaecide foam will dissipate without any encouragement. If that’s too slow for you, you could scoop it out with a net.

A Pound of Cure Is Worth an Ounce of Prevention

We’re stating the obvious. You can prevent your pool pump from agitating foam back into your pool by keeping pH, calcium, and chlorine in balance. Just to remind, those chemical values are:

  • pH: 7.5 PPM 
  • Calcium
    • Fiberglass and Vinyl: 175 to 225 PPM
    • Concrete and Plaster: 200 to 275 PPM
  • Chlorine: 1 to 3 PPM

Common Questions About Pool Foam

Is It Safe to Swim in Foamy Pool Water?

Yes, as long as your chemicals are balanced, swimming in foamy pool water should be safe.  While it’s probably safe, it’s also gross. You should probably just clean those nasty waters.

Why Is My Pool Foamy After Adding Shock?

When adding cal-hypo shock to your swimming pool, white foam might briefly overtake the water’s surface. This shouldn’t be a cause for concern. The foam is the pool shock and should clear up within the next 30 minutes.

Some of the pool shock’s calcium and salt crystals will drop to the bottom, and some will sit on the surface. Either way, it will dissolve and dissipate without any encouragement from the pool owner.

What Is the White Stuff Floating on Top of My Pool?

Some describe this as foamy mucus-like shredded toilet paper, and others just call it “white stuff.” Either way, it is likely to be either dead algae or living mold. If there was a recent algae genocide in your pool, that’s likely to be what this “white stuff” is. If not, you’re probably dealing with white water mold.

Why Is My Pool Green and Foamy?

The green and foamy mess in your pool are likely to be green algae. There are several conditions that will create the ideal habitat for green algae to overtake your pool. It would be best to avoid them, so here they are:

1. High pH water
2. Stagnant water
3. Dark and Shady places
4. Not enough sanitizer

The Pool Care Handbook & Video Course

by Swim University
This is an illustrated e-book with detailed videos and step-by-step instructions on how to best care for your swimming pool. 
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