As a new pool owner (ours was just finished a couple of months ago) I'm curious about whether there's any need to ever adjust the skimmer or main drain valves. We have a valve for each of our two skimmers and one for the main drain. Are these always just left wide open, or is there a procedure I should follow to properly adjust each one?
(I ask because it seems to take forever for the really fine stuff that floats on the water to make it to either skimmer and, subsequently, to the filter for removal. These "floaters" are too small to catch with our leaf rake).