this is the only AC filter i have so i dont know much about them. i may not need new filters then. i have an emperor 350 but i am using a really small impeller on it now because the old one is broken and its doesnt move much water, so i really think it just needs a new impeller. i had no idea i could just buy a new motor for a AC 200 filter. im just not sure if the is the real problem or not.