I got one of those boxes of joint compound, dumped it into a Homer bucket
and have been using it to do the mudding on my ever present drywall jobs. I
use a layer of water on top of it to keep it fresh, plus I also keep a
plastic cover over it to keep the buggies out and the cat hair out of it.

How long does it last if kept this way? I noticed once that a couple of
patches of green mold formed on the margins where the water wasn't totally
covering it. I wiped it away and recovered it and haven't seen any return.

Should I toss it at this point, its about 2 months old, still handles like
joint compound and appears to do a perfectly fine job. Waste not want
ot - ehh?