I added de to our skimmer two days ago. 4lbs diluted with pool water in a bucket. We got the filter used and i found a manual online that said to add 4lbs for our model pro clean de Cartridge filter model pcde-40. Now I have de in the bottom of the pool. I vacuumed the pool yesterday and this morning there is more de on the bottom. Don't know what to do now. I'm confused because I can't find anything on de cartridge filters. Any ideas.