foamy water

[DrSteveF]

My pool water is foamy. Any suggestions?

[PoolDoc]

Yep. Tell us what you've put in it, test it, tell us how many gallons it has, how you filter it, and what or who's been in it, and so on.

But, the most common cause of foamy POOL (not spa) water is the use of cheap algaecides, based on linear quaternary ammonia compounds. (Also sometimes used as cleaners for medical work surfaces)