Let me start out by saying I have had my pool for 18 years and have never really had any issues. But boy did I create one yesterday. My wife had a woman over a few days ago who had some sort of self bronzer on, which I attribute to an oil sheen I first noticed on the water surface that night. I went to clean out one of the skimmers yesterday and it was full of this oily junk and it took major hosing to get it all off. So, I decided it was probably in the filter too, so I backwashed the DE filter quite a while to get it all out. The phone rang so I shut down the pump while I talked on the phone for a while. When I was done I mixed up 7.5 pounds of DE in a bucket of water, turned on the pump and proceeded to pour it into the skimmer as I always do. After a short while I noticed that no water was going into the pool, and then I just said OH CRUD. I had forgotten to turn the valve from backwash to filter. My first instinct (which was obviously wrong) was that I just flushed 7.5 pounds of DE to waste. Was a little annoyed that I wasted money but no big deal. Shut the pump off turned it to filter and turned it back on. What I observed next was I got to see exactly the path of water flow in my pool as I now pumped 7.5 pounds of DE into the pool. Stupid me had actually precoated the wrong side of the filter. Had I just turned the valve to waste I would have been OK, but instead without thinking I flushed it all into the pool. The pool turned into a cloudy mess. So I recoated the filter and turned it back on. I manually vacuumed the pool and have my robot going several times a day to get all the DE out. It is not too terrible today but still a little cloudy with some film of DE on the floor. Keep taking the robot out and cleaning all the DE out of it and putting it back into the pool. I wonder how long it will take to fix this stupid mistake.