I was using a 200Litre upflow tank for a while and using only the top half of long (months) settled drums, then settling for 2 weeks or more, then into a 5 micron bag and it was immediately clogging the bag with fat. So I stopped going straight to the 5 micron and went to the woolies bag first instead. Lots of fat stopped in the woolies bag so I stopped using the upflow and went back to the old system of:
Long settling in 20litre drums, pour till fat appears into woolies bag, tap off 2" above bottom and pour into 5 micron bag, tap off 2" above bottom into storage containers, pump through 1 micron cartridge into vehicle tank.

I can process about 300 litres/week without actually setting aside any time to do it, just doing some transfers whenever passing. Say 10 - 15 minutes total/day.