I put the 5th coat of resin on it this morning. The kit says not to do more than 2 a day, and that a minimum of 3 is required. Since I have some resin left I'm going to put a 6th coat on it this afternoon and then call it done. The instructions say that it will remain flexible for a few days, so I'm thinking I'm going to wait until the weekend to fill the tank.
What's most interesting about it (to me anyway) is that it does appear to be melting into the tank like the instructions say. It's very thick and you glob it on as thick as you can without running or dripping. But after sitting overnight the repair is flat and smooth. This is what it looks like this morning (it's not actually 2 different colors, it's the sun hitting one part of it but not the other):
The true test is going to be if it has really bonded to the tank or is that giant patch just going to break off under a load. I prepared the surface per the instructions so fingers crossed....
The instructions say the stuff can be used for cracks, holes, refastening valve assemblies that have been torn from tanks, altering tanks or custom-fabricating tanks. The repair is stronger than the original tank. The instruction sheet goes on to say it was invented in 1983 by an RV Tech that had a need for a quick fix for holding tanks. After leaving the business he forgot about the stuff until he bought an RV with a broken holding tank. Being retired, and needing cash, he started to market the stuff. It has a money back guarantee, too.