i picked up some oil from a Chinese restaurant today and tried to set it through my first strainer, which is a piece of a flannel sheet. the first 5 gallons of wvo i sent through it was left over v/o from our turkey fryer. it passed through the "filter" rather quickly and got a ton of junk out. now the oil from the Chinese restaurant is alot darker and ticker and would not go through the sheet, so i tried straining it through a window screen first then through the sheet, but it still wouldnt go through the sheet. are they maybe using some sort of different oil to fry that is not any good? or am i doing something wrong? is this oil ok to use eventually?

thanks guys,
brian