<<Does anyone have any easy test to figure whther it's fresh or saltwater ? I don't want to taste it because the bilge is a bit oily .>> Rob, Collect a few teaspoons of water, put it in a shot glass and let the oil rise to the top. Remove a bit of the clear liquid with an eyedropper. Taste but don't swallow. What the hell - just stick you finger in and taste it. A bit of bilge oil never hurt anybody. Larry Z