What does foam in my pool mean and how do I fix it?

Foam in your pool means your chemistry is off—usually too much organic gunk (lotions, oils, sweat) or high total dissolved solids. Check chlorine first; low sanitizer lets algae and bacteria party, so shock the pool hard. Then test calcium hardness and pH—low calcium makes water sudsy, so add calcium increaser; high pH needs muriatic acid. If that doesn’t work, use a phosphate remover or partially drain and refill if TDS is high. Don’t bother with anti-foam products—they just mask the problem.