Answer:
DE Filter - 1hr per 10 degrees (Summer - 100 degrees = 10 hrs. per day)
Cartridge Filter - 1hr per 10 degrees (Summer - 100 degrees = 10 hrs. per day)
Sand Filter - 1hr per 10 degrees (Except in the spring and summer months, that’s when we recommend 12-14 hrs. per day for sand filters)
****THESE ARE HIGHLY RECOMMENDED TIMES****
If filters become clogged and are not backwashed or cleaned, or you do not adhere to these recommended times then your pool may not look its best and will start accumulating dead algae and organic matter