Filter Size to Pool Size Another rule of thumb I have for pool filter size is to look at the swimming pool size in gallons. If you've never calculated this before, take some measurements. The formula is Length x Width x Average Depth x 7.5, for rectangular pools. For oval pools, change the multiplier from 7.5 to 5.9.Jun 7, 2013
How much sand does a Hayward filter hold?
Filter System Sand Needed
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Hayward S210 T 20" Sand Fitler System 200 lbs
Hayward S230 T 23" Sand Fitler System 250 lbs
Pentair SD40 Sand Filter 150 lbs
AquaPro 19" Sand Filter System 150 lbs
What size sand filter do I need for a 15000 gallon pool?