I've finally been able to leak test my grey (black) tank, and alas, there's a leak.
I purchased a Class A Customs 40 gallon tank
, which comes with a 3in PVC adapter connected to the tank, and in between there's a butyl-type putty, with a hose clamp around the connection. The hose clamp was never super tight, and when I noticed water dripping from the area where the putty is, I first squished the putty around the connection, which didn't help, and then tightened the hose clamp, which also didn't help.
I've been unable to find other people with this same issue, and thus, solutions to this issue, more putty? I'd cover the seam with flex pipe if I hadn't immediately elbowed out of the tank. I tried pushing the connections together even more, which pushed the putty out of the seam (there was always about 1/4in of the connection that wasn't fully engaged, just putty, and Class A Customs says not to remove the 3" pipe, so I didn't bother pushing it together more before installing because it seemed pretty solid).
Any suggestions would be appreciated!