You really should get a new jug, but if you want to use it for the rest of the season try JB weld.. Be sure you make V in the crack with a dremel, burnish the area so the JB weld has something to grip into.. The stuff is great and should last for a while.. You most make sure the area is very clean before applying.. Get the marine version, it really works well.. I have used it on the tuned pipes to fix leaks.. Let it setup for about 20-25 minutes after you mix so it won't run out of the crack.. I always use a plastic knife to apply.. You have nothing to loose, just keep an eye on it.. The only problem with crackes is that they tend to get bigger with vibration unless you drill a small hole at the bottom of it to stop the spread... good luck on whatever you decide...