Just bought a house last fall with a pool. Trying to get it going for the first time this year. I have been able to clear the water and balance the chemistry. However, I notice D.E. accumulating in the deep end of my pool. I thought that perhaps I should flush my filter (Hayward Perflex). First, I vacuumed the pool clean, then began the backflush process. It was then that I noticed the D.E. was coming out of my drain. I finished the filter cleaning and am currently running the pump. Should this fix the problem, or will I find D.E. returning as soon as I stop the circulation? Any thoughts or suggestions would be greatly appreciated.