

Here’s a simple guide on how to avoid foam forming in your spa or swim spa.
The foam that forms in Spas is basically the same as sea foam. The difference is only in the chemical make-up of the foam.
Spa foam will form from the combination of water, air and surfactants. Surfactants are molecules that reduce the surface tension of liquids. And with Spas, when the water tension in water reduces we increase in the potential for oil and water to mix.
Spa water contains a variety of surfactants. These surfactants will exist in the water regardless of how well we balance our spa waters chemistry. However if we fail to properly manage our spas water chemistry, the level of surfactants will rise. And as this happens, water gets between the surfactants to form bubbles. And the more bubbles you end up with spa foam!
Balanced spa water will minimise the number of surfactants. The spa water becomes mixed with the sanitising chemicals you've added to the water. And this mix of the water and chemicals will neutralise most of the surfactants in the water. But when you fail to adequately balance your water you get more surfactants and that's the perfect recipe for bubbles which lead to foam forming.
There are three main sources of sulfactants. Let's look at what they are and how we can miminise them.
Detergents from bathers and body lotions such as moisturisers, shampoos, conditioners, makeup and deodorant can enter the spa water. When this happens the sanitising chemicals have to work that much harder. This is why it's a great idea to rinse prior to entering your spa. Body lotions and detergents in the water will directly contribute to a rise in surfactants in the water.
Beer, wine and sugary drinks entering the spa water you also produce more surfactants. A splash here and there of will add up, even on the top side of the spa. And this will ultimately find it's way into your spa water leading to more surfactants. More surfactants wull eventually mean more spa foam.
Skin cells, oils from human bodies are going to lead to an increase in surfactants. Prevening this is the main role of spa sanitisers which neutralise these elements in the water. Preventing these elements entering the spa is easy, we just rinse prior to entering the spa. Prevention is much easier than cure! And now you know if you don't you are contributing to the foam you may be experiencing on your spa water.
A quick rinse before you hop into your spa will remove any moisturisers, shampoos, conditioners, makeup and deodorant. You will easily prevent them from entering the spa water and mimise a foam forming situation. This is your best prevention method.
Correct water balance ensures that equipment and surfaces are protected and that water is comfortable for bathers. It also prevents the build-up of surfactants which lead to spa foam.
Regularly test your water using test strips, and adjust your pH, alkalinity and sanitiser levels as required. Also check for total dissolved solids (TDS) which are the number of surfactants present in the water.
If you have spa foam forming you have a build up of sulfancants in the water. If this is the case often it's best to simply drain, clean and refil the spa.
Here is how you do it:
Step 1: Turn-off main electrical breaker to spa.
Step 2: Locate drain spout below equipment compartment door.
Step 3: Pull the drain spout out with a slight clockwise turn. Note: Drain spout is fully extended at approximately 50mm. Use pliers if needed./strong>
Step 4: Remove drain cap.
Step 5: Attach a standard garden hose. Push the drain spout in halfway to actuate the drain.Note: The Spa will drain about 20 litres per minute. Ensure that the drainage is in an area safely away from windowwells or basement entries.Step 6: Once the spa is fully drained, pull the drain spout out all the way, remove hose, replace the drain cap and push drain in all the way.
Step 6: Once the spa is fully drained, pull the drain spout out all the way, remove hose, replace the drain cap and push drain in all the way.
For a quick fix, you can use Anti-Foam chemicals. These chemicals will solve the foam issue temporarily but they will not remove the underlying problem, which is the build-up of surfactants. If you have a serious spa foam issue you need to drain and refill your spa to clear it once and for all.
Correcting Spa Foam is relatively straightforward. Remember prevention is easier than cure, so rinse before entering your spa. And balance your water regularly to prevent the build-up of surfactants. And if the foam does form follow the best practice to drain, clean and refill your spa.
Enjoy your foam free spa!
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