rainwater and temperature of water

most people know about letting it sit to remove the chlorine, or the pH balance

looking out of my window and seeing it pour it down set me on a thought,

but i have no information on rainwater vs. water, or water temperature.

just a thought, never seen it any topic on RIU...might have missed them though

well first makes sure it not illegal in your area to collect and store rain water. Water rights are a big industry! Rain is usually very clean unless you live near a pollution source like an industrial zoned area (acid rain)... other than that your looking at great water source. Now if you collect it off your roof beware of the chance of foreign debris, and maybe even picking up some petroleum residue from asphalt shingle roofs.