You want to collect rainwater off your roof?- hardly "food quality" water. A garbage can at the end of the drainspout should work. Breeding grounds for mosquitos can be a problem with open rain barrels.

Regarding mosquitoes. I have a couple of cattle tanks during the summer months to which I put a few $0.25 goldfish from Walmart. This summer after catching some Bluegills I tried them, they also did nicely. They became quite tame too from tossing in an earth worm occasionally to supplement their diet. 8-) You may have to put a screen over barrel to keep from loosing them during rain however.
Gary

A plastic trash can should be fine to use to collect water for your plants. I use 5 gallon buckets plastic storage tubs and whatever else I may have collecting dust out in the garage.

Penny

Cliff-

If you're looking for something bigger, consider asking your local carwash place. We got 3-4 big, heavy-duty plastic containers from them. We had to wash the insides well because it had contained their dry soap but it washed away nicely and we've had no problems using them as a rain barrel and cold-frame during the winter.

-Rini

Thanks, all.
Now it's just a matter of finding the cheapest barrel or can.
30 gal. would be the smallest. I would like to run 2 or 3 or more if I have room. Maybe I should start small. :)
Thanks again, Cliff