ATF: Big Country - My trailer is leaking all over the concrete.

Grey water tank from shower starts leaking profusely when the tank level is over half full into the belly and on to the concrete pad.
This being a 2012 Heartland Big Country 3650RL, we are the original owners and it just started this winter. The trailer hasn't been moved in 5 months.
Oh and the sewer smell is atrocious!
What happened?

Do you have tank heating pads? If you run them with no water in the tank you can burn a hole in the tank.

Since it only leaks when half full, you may have developed a stress crack above the tank outlet, or the tank may be actually full and leaking from around the vent pipe on the top of the tank. Time to pull down the coroplast and eyeball the tank.

Have fun with that.
Sorry you are having such problems, never a fun thing to tackle.
Good luck!

Sent from my LGL41C using Tapatalk