I was reading the section here on how to clean your de filter, it's pretty much how I do it. But it mentioned a "float diverter", I've never heard of, or seen one. Is it necessary? My skimmer has 2 holes, with a flap that you can slide over one or the other. Does that flap take place of the diverter? If so, what position should the flap be? I have a 2" line from drain (2 drains), and a 2" line from the skimmer.