We encourage swim spa-owning customers to make sure they drain their spa water every three to four months. By adding chemicals intended to keep your spa water clean, you will eventually be left with overly-saturated water. Refraining to cater to this natural build-up will result in cloudy, funky-smelling water. If you are using your spa every day, water saturation can happen much more quickly, and the need to drain your spas water may be more frequent.