I have a 22K IG pool with spillover spa, two returns, two main drains and 1 skimmer. I have a 1 1/2 HP pump with 48 Sq Ft DE Pro Grid Hayward Filter and 1.5 inch lines. I did not pick out or buy the filter but the pro grid is real easy to open (loosen metal belt/clasp around the side) and then remove filter 'fingers'. I am not sure of the cost but I think it was > $600.