We have an aboveground Intex Pool 20' x 48" pool. We bought it last spring the pump/filter is going out. We have a SWP attached to it. I need suggestions on which pump we should get. Another cartidge or sand filter? Pros. vs Cons? I've had a hard time with my pool this year and now I'm pretty sure it's b/c the pump/filter has been going out! GO figure!