Originally Posted by Neverhome
I agree with keeping the black tank closed until ready to flush. I have always done the same with the gray tank because I am wary of sewer gas coming into the RV. Has anyone experienced that by leaving the gray valve open?
I never have and I'd say that a good chunk of folks leave the grey open and a good chunk leave it closed. You can also do a p-trap bend in your stinky-slinky which will stop odors if you think you might get them - but this won't stop critters (if you worry about such things). I think with such a mixed bag of opinions on the matter it's pretty safe to do whatever you feel most comfortable with on the grey tank. But do begin to save up grey water at the end of your black for a good hose rinse.