DO NOT GO BY HP, the criteria for a pool with a single pump running the cleaning system along with the filter and possibly the heater is that you need a pump that products a minimum of 65 gpm at 80 foot of head. On a pool with a booster pump operating the cleaning system you will need 60 gpm at 65 ft. of head. If the pool store does not know how to find this information then you are buying from the wrong place!