I believe the RV antifreeze is made of propylene glycol,a common food
ingredient.(although THAT makes no sense to me!) I always just drain mine in
winter(when I'm not winter camping!) and run the faucet till it's dry. Never
had a breakage yet! You could,if you didn't want to use the antifreeze and
were not trusting all the water was out of the faucet,blow pressurized air
through to clear it all.
Karl