Rain Water Collection Systems?

[jrodpad]

I've been poking around on the beginner Discussion board for a bit and I've noticed that more than a few members cut their tap water with rain water before hydrating their orchids.

For all those who use all or part rainwater, how do you collect the rainwater? Does everyone use a rain barrel? It seems like an overkill if you have a small orchid collection (like me). Also, can you use a rain barrel with an asphalt shingled roof, or would the chemicals from the roof leach into the rainwater?

If not a rain barrel, then how? Can this be as simple as putting a plastic bucket in the backyard with a screen over the top? Will the bucket begin to grow things?

I could just be wildly over complicating this - but I don't want to harm the collection....

Thanks!

- J