Also if you don't have some kind of siphon tool, pump, etc., here's a neat way to siphon. Get a length of suitable hose, cut a small slit in the end, put the other end in the tank, stick an air gun in the slit, and blow out toward the end. That will get the siphoning action started. Beats trying to suck on the hose to get it started.
187-8749_IMG by
grand73am, on Flickr