The pool/spa should be closed anytime an immediate and imminent health risk exists. These could include the following: excessive water cloudiness (the main drain is not visible); no free residual level of disinfectant/sanitizer (e.g., chlorine); the filtration and/or automatic disinfection system is not operable; the covers over the main drain or the equalizer lines are broken or missing or there is a suction hazard; the underwater light fixture has water in it; chemicals are added to the water and sufficient time has not elapsed for proper mixing; or any time you feel there is a health risk to patrons.