First I'm a rookie at this as you can probably tell by my question. Just recently had installed a 16x32 inground pool. Now I backfilled with a sand mixture to make sure the area compacts well now because of a few windy days the bottom of the pool is filled with sand. Now I have a Hayward DE ec65. Now when I vacuum I can only do a small amount because the filter pressure gets up and the filter fills with sand. I bump it and I'm able to do a bit more but soon after I need to dissemble clean and add DE. I'm wondering why cant I turn the main drain a 3/4 way close, then vacuum as I do through the skimmer but open the back wash valve on the filter and rather all the sand sit in the filter it will go out the backwash hose. Might allow me to vacuum longer. Now I know I will loose pool water but will that damage the filter? Also do I lose pressure at the skimmer with that open? The sand is amazing because is becomes almost like cement in the hoses. I have successfully cleaned out the filter and added the correct DE each time i vacuumed and I'm very comfortable with that. Just trying to figure out an easier way to do this.