Pretty much agree with Glenn on this one, forget the silly things and get on with some RVing fun.
Save that ice for some adult libation, my take and my take only, not meaning to hurt anyone's feelings, but, if I am gonna spend $$ for ice, I want to use it to enjoy, not dump down the cra**er.
We do dump some Calgon down there now and then, the laundry stuff, this stuff:
http://www.homesolutionsnews.us/calgon/