I stopped using filter socks before the skimmer compartment for 2 reasons first they are a PITA to clean and second I think it's better to let the skimmer to skim out the bad stuff from the DT and then filter the water leaving the skimmer compartment. I use rolled filter media in the narrow bubble trap compartment just before the water goes to the return pump compartment so the returning water to the DT is very clean. There is all kinds of opinions on sumps and there use , this configuration works very well for me and my DT water is pristine all the time.
