On my pool I have the main drain that is covered but does not have a Anti entrapment covers. I know the pool gets suction as I feel it in the skimmer where the basket is. When I go down and feel around the drain cover there is no suction at all. I know you are supposed to install Anti entrapment suction covers to prevent people from being pull down as it usually pulls in from the side and not the top. So is there a reason I have no suction by the drain cover?