OK so I manage a small apartment complex that has a pool. The De filter is getting to be a pain in the butt, especially now when we just opened the pool and are trying to get it ready for the season. So Im ready to swap it out for a sand filter. It being a commercial pool differs the requirements a bit compared to a residential pool. Im required to turn over water more often (technically 4 times a day) Its about a 50k gallon pool averaged out between the deep and shallow and the 925 lb filter says its can turn over 101k gallons every 12 hours according to the pentair specs, so that would be perfect. But the dealer is afraid the pump doesn't have enough GPM to properly back wash a filter that large. Is this really a concern? Its 3" suction and 2.5" return plumbing, 20x50 pool with a 10 foot deep end, 3 hp pentair variable pump powering the system. I have no idea what the GPM is of the pump. But I would think a 3 hp pump would be powerful enough to backwash the filter. The plumbing only has 2 90* bends. So Help me out, is it over kill to put in a half ton sand filter. The dealer is recommending a 500 or 600 pound filter. But I thought with filters the bigger the better. Im just trying to reduce the required maintenance. This being a rental the less maintenance the better, so I'm not out there every week pressure washing a de cartridge getting my self covered in green slime. Thanks so much!