Summer of 2019 we bought an Intex 22x52 pool. It came with the awful cartridge pump. Suffered thru the summer with that. The following spring, I purchased an intex sand filter pump 2800gph. I sanitize with a floater with two 3 inch chlorine tabs. I have the intex robot vacuum.. I also have the intex skimmer. I wonder if the pump is big enough for the pool.? The water definitely moves. The robot moves for awhile but I dont think my hose for that goes to the opposite side of pool as well. I use a test strip kit, I have the testing kit.. my ph always seems high, I use ph down. My water is rarely clear and clean looking. Lots of green water, lots of algae. When hooking up vaccuum with head, I attach hose to port that I remove the grid from and turn filter to waste. I work on the pool more then I enjoy it. Any info, helpful tips you can give me would be much appreciated!