Rain Water


So, where I live, we’re in rainy season. And while I don’t mind trekking out to collect RO water from my local pet store, I’m kinda thinking of skipping a step and setting up a rain barrel system to collect rain water to use that for my Grobo. Currently using RO/Distilled water. Would rain water be more beneficial? Or not really make much of a difference.




I wouldn’t use rain water as you don’t know the pollution levels in your area … like how much acidity the water is holding among whatever else’s goes into rain pollution … I’m not sure if boiling or leaving the water without a cap on for few days help to get everything out like it does with chlorine … but @Stephen would know those are just my thoughts and guesses



I have a rain barrel outside and have used it co tj hally for my cough outdoor plants and they actually look better than the indoor ones. Especially considering its snowing outside atm



Hey Todd, I’d take a gallon jug fill her up with your rain water, bring it into your house to get to room temp (maybe a day or two) and if you have ppm/ec pen and ph pen I’d take readings and see where it’s at. If you live in a rural area your rain water should be fine, but I’d check it first. Great free resource, and then you can use your drain water from your grobo to feed other plants you might have. I used rain water last year here in ak and it was great.



Thanks Jerry. Seems like a bit more work than I want to do lol. My water runoff is or was coloured yellow for most of the year due to the park area i live in. I only started adding notes after about a month of growth. Going to have to transplant to pots this weekend due to snow.

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Here are the pH values of rainwater across the US of Eh from the EPA cir.1999 …


BUT, it’s not pH that really matters here. It’s EC. How much contaminate is being carried off your roof into your barrel is the question. I’m with @Osage above. Gather some and test it. If the EC is below 0.5, you might consider trying some on your grow.

Good luck, RO always works well…




Yikes. Given the fact that I’m in the red… I might want to just stick with the RO water. Thanks all!

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yep you got it Stephen as usual, but I always ph’d the rain water to see where its at. If it is a really high ph or really low ph but ec/ppm is good, then the decision for me was would it be worth it money wise using more ph up/down. That would be a bit of an extreme case really, but if your ro or other available water is a better ph with relatively same ec, then I would go with latter and not the former. It just provides one with more informed choices, which in the end will benefit your plant and your overall experience. Yayyyyyyy its Friday. Happy weekend all