Bursting the Bubble

One of the biggest problems spa owners deal with is foamy water, so one of the biggest problems spa retailers face is customers complaining about foamy water.  

Several things can cause foamy water, and different solutions are available depending on the source and severity.

1. Soap residue — Soap and detergents introduced to the water by bathers are the most common cause of foaming. When people shower, shampoo their hair and wash their hands, they often, unknowingly, don’t rinse all the soap from their bodies. When that person enters the spa, the residual soap and shampoo dissolves into the spa water, and once the aerators are opened, foaming occurs.

Similarly, bathers can unwittingly introduce residual laundry detergent to the spa water through their bathing suits. When clothes are washed, some laundry detergent remains in the fabric, even after going through the rinse cycle.  

2. Body care products — Hair spray, gel, makeup, deodorant, perfume, cologne, lotions, creams, moisturizers, sunscreen and bug spray introduced to spa water by bathers can contribute to foam.

3. Improper water balance — Low pH and low calcium hardness can both naturally cause foamy water. 

4. Spa care products — Many household cleaning products, including some cleaners used in spa care and maintenance, have foaming agents added. In other words, an additive has been put into the product for no purpose other than to create foam. The truth is, foam isn’t vital for cleaning; it’s used merely for aesthetic purposes.

Many products used for cleaning filter cartridges, the underside of spa lids and the spa’s shell, along with plumbing cleaners or purge products, contain foaming agents. If the residue from these products is left behind, foaming will occur.

Remediation

Foamy water will not hurt you, but it can be annoying and isn’t aesthetically pleasing.  Defoaming agents are a short-term solution; they will suppress foam temporarily, but it will return.

Foaming caused by body care products, detergents and spa care products can be remediated the same way. To rid your spa of this type of foam, install properly cleaned filter cartridges, shock the water and increase filtration times. Multiple filter changes and shock treatments may be required. Some of the excess foam can be removed manually with a net, blown away with a leaf blower or sucked up with a vacuum. 

If the foaming is excessive or you’re looking for the quickest solution, consider refilling the spa. You’ll spend less than $11 on water and electricity to refill and heat most spas (see my June 2024 article on utility costs).

If foaming is caused by water imbalance, simply balance the hardness and pH and the foaming will subside.

Prevention

The best way to deal with foamy spa water is to prevent it from happening in the first place. Best practices include:

• Have bathers shower thoroughly before using the spa to remove soap residue and body care products from hair and skin.

• Wash bathing suits without detergent, or at a minimum, rinse them thoroughly in fresh water before wearing them into the spa.

• Maintain properly cleaned filters (see my article in the November 2024 issue on filter care).

When using spa water care products, particularly filter cleaning and purge/plumbing cleaning products, choose brands that do not contain any foaming agents.