Matt,

Bleach is okay. Exact proportions, I don't know, but a very small amount
should keep things fresh. And if you let the water stand without a cover
overnight, the bleach will dissipate, so no ill effects on the plants.

Diana

"Matthew Donadio" wrote in message
...
Hi all,

I just got a 10 gallon water cooler to store water in. The cooler is
totally opaque (it's one of the yellow Igloo pigs), but I'm thinking that
I
should add something to prevent Icky Stuff from growing in it. I have
Physan, but that's a bit expensive to be constantly using. Is household
bleach OK? How much per gallon?

Thanks.

--Matt