We have an Intex 9x18x52 Ultra Frame pool, also an upgraded 2500 gph cartridge filter. Thinking of upgrading the pump/filter again. My question has to do with the configuration of pumps and filters. It seems that from the suction side of the pool the water goes through the pump first then the filter and or leaf basket. This would make the dirty water go into the pump first. I would think you would want the water to go through the filtering system then into the pump. Why at least on mine does it suck the water straight into the pump without filtering it first. Are there any pump/filter systems that are configured to go to the filtering system first and then the pump. Is that not a good idea? Why, if not? My pool holds about 4500 gallons, any upgrade recommendations for pump/filters or is it not needed? Would like to be able to run vacuum using 25 feet of hose. Finally anyone know how powerful, (horsepower) that Intex 2500 gph cartridge type pump is? And how large the cartridge that goes with it is as well. Any help would be appreciated. Thank you.