RO/distilled water sources and method?

Hello all,

I’ve currently been watering my plants with store bought distilled water but now that they are in large pots I’m really concerned about the plastic waste I’m creating by buying gallon jugs. I’ve heard Walmart sells RO water or something in refillable 5 gallon jugs but out of curiosity how does everyone obtain and store there RO/distilled water? And if you use the 5 gallon jugs do you just lift it and dump it into a secondary watering can? Just seems a little unruly to me and was curious if there was a better solution.

With summer and its heat and humidity I run 2 dehumidifiers. One is in the grow space and the other in a bathroom. They almost provide the 4-5 gallons I need to water every 4th or 5th day. Empty them into 5 gallon food grade buckets. Supplement with rain water if short.


I just started running a humidifier myself and the thing fills 1-2 times per day and I had thought about doing that. I read conflicting viewpoints on whether it was a good idea or not due to mold and bacteria etc. I can’t see how it would be any different from distilled though.

I think I’ll run the pH and solids then start doing one of my younger plants with it. If it works out for a couple weeks l ill switch em all over.

I washed the collection tank with bleach to minimize the nasty stuff you mentioned. My tap water ppm is around 250 so it gives me more top end on nutrients or certainly keeps below max-out range. I haven’t noticed any negative effects. I think they are pretty happy - from a few days ago

Just tested the dehumidifier water and it failed pretty hard. PPM was only 60 but somehow it pHed about 4 both via color test and pH pen.

I don’t know what the heck the dehumidifier could be doing to make the water that acidic.

Honestly I just use my tap water filtered with a hydrologic small boy to take all the chlorine and such like that. Then I subtract the 170PPM from that water when I add nutes.

I have been told that ph reading of any liquid with ppm under 100 is unreliable. I tried like hell to ph my rain water (ppm <10) and distilled water. Finally asked the question and that was the reply.
Actually I am surprised by the ppm of the dehumidifier water. I wouldn’t think it would be that high. I confess though I have not stuck the pen in my water. Wait - bluelab conductivity pen is 0. My Hone Forest pen reads 21. The bluelab is new and calibrated so I will go with bluelab

@beardless I can test the distilled water fairly accurately with a chemical test because it doesn’t rely on measuring a voltage I thought. It generally comes in about 6.5 because it doesn’t take long for pure water to absorb CO2 from the air and become mild carbonic acid.

My tap water might work its got no chlorine and it runs about 120 ppm if I use the fridge filter. It’s slightly alkaline though and I would hope it’s from calcium minerals.

I should probably be worrying less about it considering I put it in my own body every day.


A chemist I am not.
Re calcium in water. I was going to mention is the lack of calcium is one drawback of using distilled

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With a small sample if you breath on your rain/distilled water you can bring the pH down to about 5.5ish.

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