The pool installer is recommending the DE filter. I have never seen a commercial pool use DE and there must be a reason. He says that the DE has better filtration but I am thinking that just back washing the filter and putting it back in operation is pretty easy vs having to pour DE in the filter each time it is backwashed (also having to have DE on hand). Pro & Cons anybody. Love them or hate them after the new wears off? Anything wrong with just a plain old sand filter? I stayed at a hotel this past weekend and peaked at the pool filtration equipment thru a crack in the fence and I saw a chlorine generator (so must have been a salt water pool), UV sanitization system, and a big old sand filter. Pool floor was little blue tile and I could see the grout lines between the tiles on the bottom of the pool so it must have been pretty clear.