Skimmers - How often do you clean them?

[Enigma]

Originally Posted by emerald crab

With that setup you're looking for trouble. Think about skimmer going crazy, overflowing. That's scary.

When the height of the fluid in the collection container (a four litre milk jug) gets to a certain point (about an inch below the opening) the flow stops from the skimmer cup and the skimmer cup overflows into the sump.

I have no idea what aligned so perfectly to allow this to happen. I didn't plan it, and I couldn't ever repeat it if I tried.