August water at 36 degrees: managing temperature, not just chemistry
By August, an unshaded villa pool in Dubai or Sharjah can sit at 34 to 38 degrees, which is warmer than most people's comfort limit and close to useless for actual swimming. Warm water also holds less dissolved oxygen and hosts bacteria more happily, so temperature is a hygiene issue as much as a comfort one. There is no chemical fix for hot water; there are only mechanical and scheduling ones.
If you are considering a chiller or a reversible heat pump, get it specified against your pool volume rather than buying on price alone. An undersized unit runs constantly, drives up the electricity bill and still leaves the water tepid. This is a job where collecting two or three written quotes with equipment model numbers pays for itself.