I have a 12' x 40" ag pool that is currently running on the standard intex style pump and filter combo that came with it. I am going to upgrade all my pipework to solid pipes and want to change my filter setup. Whats the best way to go withput spending stupid money? Im thinking some sprt of circulation pump and then maybe a sand filter/cartridge filter (whats best?) and then also going to get a swg. I alsp currently have 2 x 3kw heaters running. Any advice appreciated.