Rainwater from the roof

[leisure_man]

Is the rainwater collected from a composite roof shingle (asphalt) safe for fish?

Is anyone collecting rain water from their roof right now for their fish?

[paddysdaddy]

Good question and a valid concern. I channel rainwater to a couple of large vats containing goldfish, turtles, Cichlasoma Uropthalmos and Texas cichlids. Laziness and frugality are the real reasons, a gutter downspout is 8" from one vat and I know the water is fine. One real caution though: I allow the rain to pass down the downspout for at least 15 minutes in a hard rain before diverting it to the tubs b/c I've heard pollution from the roof is washed off by the rain the first few minutes. After that, I allow the tubs to overfill (thus accomplishing water changes rather than just refilling). I'm not sure I'd trust the water for discus or apistos but those deserve an R/O unit IMO.
The shingles on the roof are 11 years old and the dimensional variety(therefore more of the asphalt edges per square foot). Have never tested PH or DH, but the fish like it and the water tastes great.
Good luck!

[Mike Wise]

The trick is to wait for it to have rained for about 15 minutes be collecting the water. This allows for pollutants in the air and on the roof to be washed away. Then run the collected water through good quality activated carbon before using it in an aquarium. This works well for soft water cichlids. If you live where it rains a lot and often, this can provide small quantities of soft water. Snow melt works well, too. Just don't use the top or bottom couple of inches/cms. I've used it on apistos at times with no problems.

[Matt724]

I've collected rain water that way and when I tested everything, it was crystal clear. pH was dead 7.0 and everything was perfect, the only thing that sucked was that it was about 40F so it took about a day and a half (the house was pretty cold because it was dead winter) before it could get up to 70F and I could use it. A heater would probably speed it up, but is it worth it?