Do you collect and use rain water on your cannabis?
I have tested it 4 times. The first time I am discarding because I had just cleaned the barrel and I may not have rinse it out well enough.
The PH and PPM are
6.98 6
7.77 5
7.16 5
Reading 1 & 3 probably took 30 - 45 minutes to get those readings. I suspend my meter in the water and just check in to see where it is at. Today I threw some Johnsonville Brats on the grill and ate one (great brat) for dinner. The first reading was high 7’s. After my brat it was 7.16.
Does it take forever because of the low PPM? I also use much less PH down with rain water (again because of the low PPM?)
Any one else with similar experience / readings?
My plants have always loved rain water. For me, collecting if off the roof (a 5-gal bucket under the rain gutter downspout. The downspout has a nylon stretched over it to collect big debris), It needed it to rain pretty hard to clear all the pollen and “stuff” off the roof. After that I’d have 0 PPM’s and a PH of just under 6, pretty consistently.
No salt here but I collected some and mine test way up over 7 too. But most water I test is 7 or higher except distilled. Guess that why pH up/down is used??
Any reading you get from water that tests under 100 ppm is unreliable. Says so right in the Bluelab manual. This applies both for TDS and PH. There simply isn’t anything there to read.
@Myfriendis410 Is bluelab a brand tester? I got these and didnt see anything in the literature that said that. Very curious about this. I just got them and did calibrate.
didnt have rain water at the time so mixed 50/50 purified bottle water and distilled. Purified was over 7pH distilled was just over 5. Combined got 6.8 ppm 1650. Stormed yesterday so got some rain water now
The first runoff from the roof should be discarded. Once obviously clear water then capture and use like distilled. (There is a bit of N in it from cloud/rain formation too)
OK that is what I was thinking. I have to change the process I use. With tap water I PH first so I know approx. how much down to use. So far this grow I have not used any nutrients so I stop there. Then add any nutrients to the tap water and test again. If within my target of 6.25 to 6.50 I am good to go. Other wise I add more water or down to get it where I want. With rain water I need to add the nutrients first then test and adjust. If using plain rain water what then? Assume it is a a little below 7.0?
Last year is when I started collecting and using rain water. Didn’t test back then. Just figured every thing grows using rain water so should weed. When I had to switch to well water, I had problems with my first grow using only well water. I had to start testing and adjusting PH.
rain is not always good for plants. Depends on where you live. In the old days in Europe coal fired electrical plants and house heating made rain so acidic it stripped paint of houses and early cars! If you live near a major urban center where manufacturing is strong, you may get lots of chemicals in your water along with ph issues. I use lake water and dechlorinate it in big barrels. I could use rain but its unreliable especially in the summer.
I think water quality is pretty good. Not much industrial pollution more agricultural runoff affecting watershed than anything. I did PH after just adding calmag. At least in my tap water it only slightly reduces PH. It came in at 6.46 and PPM of 390. Last year I got through almost 3 complete grows using rain water and had no issues other than what I caused.
Interesting. I wouldn’t have thought that of sc BC. But then again, when traveling to Oregon I was surprised by the high arid desert plateaus east of the Cascades.
Yep we live in what is called a transition zone. Where the semi arid meets the forest. The Kamlops area is actually the extreme northern ensd of the Sonora desert there are tumble weeds there and rattlesnakes! They even shoot western movies in that area.
In late July we can often get temps in the 100 degrees American range. The average would be around 90 or so. Winter sets in like someone flipped a light switch around mid November and snow is on the ground till end of February. Planting season is typically mid may and goes to late September for hearty plants. Greenhouses extend the growing season by 2 months.
What do you have going on that generates those kind of PPM numbers? That’s to bad, how do plants survive with that much stuff in it? Our well water is 7.5 - 7.75 and around 250. You follow VPD pretty closely don’t you? I am trying to pay more attention to it especially now heading into summer etc. and with my first photos a week into 12/12. One frustrating thing is I have two hygrometers in opposite corners of the tent, same height of 2" above the canopy and the readings can be 10 percentage points different. I use the average not knowing if one or the other is wrong.
Well the 650+ ppm is rain water so it carries stuff from the roof down to the French drain that adds to it. I’ve never sat a bucket out and tested that. I don’t water my plants with it. I just tested my rain water and stuff for fun. My pond is high ppm low pH and it grows like a champ.
I do follow vpd as closely as possible but my climate falls in range most of the grow season.
there are tumble weeds there and rattlesnakes! They even shoot western movies in that area.
& 
a few times. It’s always 7 (+/- .3) pH and ppm varies from 650-1300. My tap is 6.7 (+/- .2)pH and ppm is 150-225.