Last fall, I had my heater replaced. Before they left, they forgot to turn the jets/drains back on and the piping imploded. The came back and replaced all of the bad piping. AFter they left I noticed de powder in the pool...alot of it. I called and was told that they might have overfilled a bit. This year when they opened the pool, the same thing happened with the DE. I asked again and was told the same thing. He said it shouldn't happen again. The next time I backwashed, no powder came out with the wash. I added more and it ended up in the pool again. I made a call and never got a return call back. I finally was able to reach another pool company. He said they probably blew up the filters when the pipes collapsed. Sure enough, they were shredded. He changed the filters, but we are still having the same problem. The first guy had to also change the valve because that was also damaged. Could the new valve be bad??? My new pool guy is stumped and so am I.