About a week after I got my mini sub tank.. I noticed a small crack, starting from the base leading towards the other end. It was about a quarter of the way up the tank. A couple weeks later (today), the crack is now more than half the way up the tank. I've been using Rootbeer Float in this tank... Is that the cause of the problem? Any chance I can mend this up with just superglue? No leaks from the crack yet. Not looking for a refund... I think can post some pics if it helps.