Continuing the discussion from How do I make guano tea?:
I wanted to create separate thread to discuss different types of water:
What are your opinions about use of different types of water for plant watering.
Ground water , I’m thinking would maybe be better than rain because of absorbing desolved minerals. I’m just guessing . I read some on O.G. 1.0. That rain water has a natural npk rating with a n value, just a little not much.
I always thought that rain water is very soft with hardly any EC. I wonder where could the nitrogen get from…
I myself don’t know . Just remember reading that in a post on original o.g… The person posting i can’t remember name but was a well respected member is why i tried remembering that little bit of info. But i haven’t had rain water tested so far as a fact , i dont know. My bad.
Distilled water is aggressive, standalone. It tries to absorb everything it comes into contact with. Rain, A/C and dehumidifier condensation are forms of distilled water. Acid rain and other heavy metal contaminates are direct concerns of some, it’s just what distilled water does. The longer it sits the more stable it’ll become, adding some nature will speed up the “buffering”. Something as little as some rocks in the bottom of the 'ol rain barrel can be a solution for speeding up, I used a pond BITD. If you want science talk research the science, this is a layman’s explanation. I held both a WQA and a CPO for decades.
I’m using RO/DI right now, though I never soak a plant without adding some mineral content back in. Per suggestion of “The Rev,” I add 10-15 drops of General Organics CaMg+ per gallon of water to RO/DI before use when giving straight water.
I used RO/DI in my earlier grows, too, without knowing this trick. I always suffered from magnesium deficiency back then (of course) so I ended up putting about 1/4 tsp epsom salt per gallon before use.
Untreated city tap water for my aquaponics. I change my T144 TurboKlone daily with tap, and dump the waste in the fish tank to top off the daily plant consumption and evaporation 
2 posts were merged into an existing topic: Dumme’s Aero-Soil-Aquaponics adventure
I like rain water better than anything, RO water is my next choice, and next is tap water with a handful of compost and left to sit for a few hours.
RO- I like to use it when I can, PH is more stable and lower in hydro systems but I have to fortify it because it has nothing in it.
Ground- I assume this is tap or well, I get my water tested to see what the carbonate content is as well as other things like chloramines. I use this most because its just easy to turn on the tap.
Rain/Snow- I dont use this anymore, I think I had a problem with this, springtails got into my soil, not a big deal but stuff just gets into the buckets, and ends up in the garden.
So do you keep Saltwater or Freshwater fish?
I use the same methods and also add in Silica which helps with heat stress and adds some strength to the stems.
Another thing you can do is mix your DI resins and make the PH right where you like it out of the filter. Hard to beat RODI water IMHO if you don’t mind the waste water and adding back a couple of items.
im fairly lucky that my citys tap water is not too bad, i just leave it out for a day or two to gas off some chlorine and sometimes i don’t even do that
If you throw some compost, molasses, or anything organic (used to be alive not the governments copy righted opinion) in it then the chlorine will react and gas off. Chloramine also.
From talking to hydro friends it sounds like water quality is more important in hydro than soil. Some of my best crops in soil were using city tap water, filtered through a “Brita” or “Pur” faucet filter only. The pH was 6.5. I know people a few towns away that have 7.5 tap water, that is an annoying problem with no easy fix, you have to add some kind of pH down every time.
Well water is great, as long at the pH isn’t off it’s ideal. Many houses have to use water filters on the well water though and almost all filters and softeners raise the pH to 7.0 or higher.
Just make sure you don’t let the bicarbonates build up and fluctuate your ph. Well water could be worse depending on where you live. Too many metals can toxify your plants also. Like the old saying goes location, location, location.
yes, my well water has shitloads of iron in it. I use a large PUR pitcher filter to remove most of it. Most of the people in this area have either too much iron, too much sulfur, and/or pH too low. They all have water softeners, so you need to make sure there’s a spigot in the well piping before it gets to the softener which salts the water and raises the pH above 7.0.
My well water’s pH is 6.2, perfect, but too much iron. I used KAR labs to test the water a few times. There are junkyards nearby and I was looking for petrochemical contamination.
I have gutters and a large roof, I’ve thought about rain barrels, then I wonder if any chemicals are leaching out of the asphalt roof tiles?
I catch all the rain water i can and use it fast to keep stuff from growing in it. The water is on the tiles for a very short time. You are smart to test your water. Knowledge is power.
lately I’ve been using this bad boy to filter my well water, it takes 1 gallon at a time:
https://www.pur.com/water-filter-pitchers-and-dispensers/pur-classic-18-cup-dispenser
I fill 5-gallon buckets of unflitered well water in the basement and then use the PUR filter to fill gallon jugs. Works really well. With city water you get the one that screws onto faucets. These leave the good minerals, take out chlorine, lead, iron, etc. Unfortunately they do not remove fluoride if your city adds it. RO is the only solution there. Mostly an east coast USA problem.
I am a fan of R.O. as long as that’s all it is Walmart ro has additives for flavor and as nice as it is for drinking I’m sure it is salts of some kind. However I was looking at various brands of home filters such as Brita while reading labels I saw they had an at home water test kit at under $20.00 rain water is way too sketchy due to air pollution in this area. Local water grows a black mold on your faucets and toilet I only use it for bathing and flushing
Most of the pollution in the air that can get in the water is sulfur which is good for the plant. Carbon will be in there also which is also good for the plant. Fear no rain water. 