Out neighbor put a working Hayward 1/2 HP pump and 200# sand filter on Craigslist. He ended up giving us a 3/4 one that siezed up as well. We have an Intex 15' pool with it's poor cartridge. I know we will need to tinker with hose fittings, but what other common pitfalls should we avoid? To show how green I am at this, the size of the sand filter totally floored me.