I bought my pool used last Spring. I have a SwimPro SW256T Sand Filter. Throughout the summer, I had sand blowing into the pool. I read that changing the laterals was the only way to fix it. I ordered new laterals, with the center pipe. I bought new filter sand and we replaced the laterals. When we went to turn on the pump, it just hummed. I bought a Hayward SP1580X15 Power-Flo LX Series 1-1/2-Horsepower Pump and hooked it up yesterday. As soon as I turned on the pump, you could hear sand swishing around and blowing into the pool. I could feel the sand blowing into the pool for about 2 minutes until it finally let up. I vacuumed today then back washed (didn't realize that was somethign that only needed done once a week) When I put it back onto filter, the sound of sand returned and it blew for 3 minutes until I turned my pump off.
What could be causing this? I am new to all of this pool stuff and I'm ready to give up, it seems like I just can't win. Any help would be appreciated.