Put antifreeze in black and grey after winterizing ?

Artum Snowbird wrote:
Always pour a half gallon down the black and grey tank before the winter season.

It's cheap insurance, and has never failed me. I hate failures.

X10 !

I also fill toilet with pink stuff and pour a gallon each into black and gray tank to protect the valves.

4,5 bucks for a couple of extra bottles of anti-freeze to cover all bases versus $$$$$$ to repair broken lines etc?

Seem like a no brainer! :B