do you have an open ***** or pressure driven fuge? how many passes to clear the stuff up? do you use a rough screen to get some of the stuff out before sending to the fuge? Do you heat?
I have a pressure driven fuge (108 gph) from PaBioDieselsupply
I make a min of 6 passes, and generally make 8 passes unless I'm in a hurry to fill the tank.
I don't use a screen at all, oil gets sucked up at my collection site w/ my super sucker, gets shot into my centrifuge barrel, no pre-filtering.
I don't heat, I mix my thinner (I use Kero or RUG, whichever I feel like buying) then fuge it. I did recently slap a Kats 500w heating pad on my barrell that I had laying around and thought I'd try heating again, BUT I don't think the 500w is enough to get the oil to temp. In other words it was a waste, you need a good 1000w+ to heat a 55 gallon barrel. Thats a lot of used energy
Cold filtering seems to work pretty well for me.