Here is the location of my skimmer, the drain, and the sock. They share the same zone in my sump. My sump is only 3 chambers, and is going to be reconstructed to have baffles moved to return pump side (Because i screwed up when i built it), and a larger refugium. I will free space by making my return area MUCH smaller. I thought I needed a big one and its taking up tons of space that is not required.
My sock needs to be cleaned, it foams like this when its dirty.
Here is my sump empty...
Hope you get something out of this. Everyone's sump is different. Its just how you personalize your system.