What causes foaming in hot tubs?

Foaming is not uncommon in hot tubs and be caused by poor water balance, insoluble compounds, soaps and detergents

Poor water balance
Low calcium hardness levels can sometimes promote foaming.

Insoluble Compounds
Buildup of insoluble compounds, such as perspiration, cosmetics, etc. Spas should be shocked frequently. They should also be drained periodically.

To determine how often to drain your spa, use the following formula:

Volume / 3 / Average Daily Bather Load = Number of days between drains

Use of Algicide
Most Algicides foam unless they specifically state otherwise. If a foaming Algicide has been added to a spa, it may be necessary to drain.

Soaps and other foreign substances
Detergents from poorly rinsed bathing suits can cause extensive foaming, as can any fragrances, bath oils or other warm water scents not especially designed for spa use. Read labels carefully when selecting any kind of spa fragrance.

Cleaning agents
Spas should not be cleaned with household cleaners. If the water line is cleaned with anything that was not designed for spa use, it can cause foaming or buildup. Household cleaning products should also not be used when the spa is drained. It is very difficult to completely rinse the buildup off the spa walls, and when the spa is filled, this film can cause foaming.

If none of the above are the cause of the foaming problem, or the foaming is slight, use SpaGuard® Anti-Foam to eliminate existing foam from the spa surface.