I apologize if this is in the wrong forum but I have a couple questions regarding DE filters.
First I have an 16.5k pool with a 1k spa attached this is cleaned by a Hayward Pro-Grid DE 6020. I am wondering if there are any recommendations for how long to back wash. I have the back wash plumbed to a tree so I don't waste the water and usually let it go for about 5 minutes. The water doesn't completely go clear but looks pretty good.
Second, when refilling the DE thru the skimmer the filter calls for about 7.5 lbs of DE and I was wondering what is the best method for measuring this? I have a large scoop, I believe is 4 cups that I use now. I typically put around 9 of these in.