Actually, two questions!
1. Every post I see about how much DE to put in a filter references the DE scoops available that hold 1 lb of DE. I have one of these scoops and it says (on the botom of the scoop) that one scoop should be used for each 5 sq.ft. of filter surface. I have a Hayward 4800 (48 sq.ft.) so, according to the scoop, I should be using about 7 1/2 scoops (or 7 1/2 lbs) for a completely clean filter. However, the filter says the maximum is 6 lbs! I was using 6 scoops last year and it worked fairly well. I increased it to 7.5 this year and my filter seems to be clogging too often and I think I'm putting too much DE in. I don't have a scale to measure, so which should I believe?
2. All of the wonderful postings from 'waste' about DE filter maintenance say I should wait until all air is out of the filter before adding the DE (which makes sense). However, this sometimes takes about 10-15 minutes with my filter and other readings say I should NEVER run my filter without DE for more than a minute or so for fear of damaging the filter elements. So....which is really right?