I used JB Weld to fix a large crack in mine about 1.5 years ago and it is
still holding!
The trick was applying the goo through the toilet flap and over the crack.
Now my gray water leaks at 3/4 full.....it's on my list.
Actually I think it's related to the shower drain cause it also leaks when I
use the shower weather or not the tank has anything it.
AlanT
Phx Az
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