This is my first post and I'm looking for some help. I just installed a 1600 ghp Intex sand filter on my 15'X42" Intex pool (3860 gallons) to replace the vertical skimmer/filter pump. I've installed per the instructions, using quikrete pool sand, a GAME 4552 Skim Filter Pump Adapter, and Intex SWG system. I've operated this on my pool everyday for at least 5 hours and three times overnight since I got it 5 days ago, with the water still cloudy. I have some dirt on the bottom and have tried to vacuum but each time I put the vacuum adapter on the top of the vertical filter housing, my pressure drops to zero and my pumps starts to cavitate. I have to remove the vacuum adapter and restart the pump to allow it to prime and not sound like it's still cavitating, and on top of that, when the pump starts I have muddy water being injected back into my pool. I've done some reading on this forum and have seen where some think the quikrete pool sand may be the issue, but I'm not convinced. I also may think that the GAME adapter may be too restrictive, going down to less than 1.25", providing even less water for the pump when I put the vacuum adapter on. I'm disappointed to this point, after having done a lot of reading and having gotten excited about the changes my pool would undergo with a sand filter as opposed to the factory paper filter. Any help would be appreciated.