We currently have a 24" AGP with a Hayward 180ST filter and an AO Smith Pump (pix attached). It appears to be 1HP and will be replacing it if it dies, or possibly sooner. I dont know much about pumps or filters(am trying to learn), but I am thinking of eventually replacing the sand filter with a cartridge filter as well. I really have no clue what to get, but the pump will be replaced before the filter. The pump has a three prong config, that is round (metal prongs form a circle). Is this 115 or 220? Pump says 115 on it. I know that I want something efficient as I'd like to save on electricity if possbible. Any help is greatly appreciated. Thanks!