Black tank, am I in trouble?

[Bnrc73]

I'll try to make this as short as possible. Coming home from wintering in Texas, after our overnight in southern Kansas, we winterized the trailer knowing our next stop in Nebraska was going to be cold. We did use the black tank that night and the next for certain functions, no 2, and rinsing each time with RV antifreeze figuring on running in some fresh water and dumping for good for the last travel day home. After filling to over 2/3rds I went to dump and you guessed it, the valve was frozen. Stumped on what to do, I dumped in a gallon of RV antifreeze and two gallon of 50/50 auto antifreeze. Figuring a 300 mile trip would mix everything up and stop it from freezing. When we got home, 25 degrees, the tank seems to be unfrozen. It will sit now for two weeks till the city's dump station will be open and hopefully warm enough to open the valve. Sorry for the length..Im just hoping somebody out there will say it's going to be ok.

[dalford]

Do you have tank heaters? Turn them on and leave them on if you have shore power at home.

[rockfordroo]

Dumping auto antifreeze into the city's dump station is going to be a big NO-NO (read ILLEGAL).

You should NEVER have put that in your black tank.