What is wrong with my hot tub water?
Tap what you see and smell. You get the likely causes, cheapest to check first, how to confirm each one in a couple of minutes, and whether it is safe to get in tonight.
What do you see?
Tap everything that applies.
What do you smell?
Most likely causes
Pick at least one thing you see or smell.
Where this comes from: our guides to cloudy water, green water, foam, smells and slime, which draw on the CDC, water-care standards and equipment makers. Ranges used: free chlorine or bromine 3-5 ppm, combined chlorine 0.5 ppm, alkalinity 80-120 ppm, pH 7.2-7.8. For doses, use the dose calculator.