FWIW I have discovered a situation with our flex-tanks that others might like to know about.
Per my earlier note, above, I made repairs
to our water-tank using contact cement per suggestions by GordMay. Upon reinstalling the tanks, however, I discovered another leakage issue that I hadn't noticed earlier.
In short, after reinstalling the tank, I tightened all of the fittings and filled the tank, but left it uncovered so I could check for leaks
the next morning (I drew circles around each fitting with a water-based pen so that any seepage would be revealed). Upon checking I discovered seepage around the base of the fill fitting that had evidently loosened over night. While I sat there pondering the matter I noticed that every time the boat rocked, the fill hose, which lays on top of the tank and still had water
in it, moved somewhat with respect to the tank itself. Evidently, this repeated movement worked the filler throat back and forth ever so slightly, but enough to loosen the fitting sufficiently to cause seepage.
I have retightened the fitting and secured the hose to the top of the bladder with a number of layers of duct-tape to prevent this differential movement in the future and will now check our other water tank, and our holding tank
, to ensure that a similar situation has not developed with these. A holding tank
could be particularly problemsome as even the slightest leak could allow oders to escape.