4 Reasons Your Pool Has Foam and How to Fix It

Low calcium hardness Soft water foams like a bubble bath. Test your water and add calcium increaser if levels are low.

Leftover algaecide or clarifier These chemicals can cause foam. Shock the pool and run the filter longer to clear them out.

Detergent from swimsuits Someone jumped in with too much laundry detergent on their suit. This is a common cause of sudden foam.

High phosphates from leaves or runoff Less common, but treat with a phosphate remover if tests confirm it. Avoid using a defoamer as a permanent fix—it only masks the problem.