Well, yes, a bigger filter should fix that. If you look at my sig, the T210 is a 22" 200# sand filter and you can vacuum on High without a problem. But the 200# filter is really the smallest I can use with this pump. Had I known in 2002 what I know now, I would have gotten the 250# or 300# filter. But it's OK. I really think you don't need anything bigger than 300#, max. Even that's overkill but....I'm betting you won't have anymore problems. WaterMom, our other mod, has a 300# sand filter with, I believe, a 3/4 hp pump for about the same size pool as you and has no problems with it.