Anyone else have issues raising ph levels?. I’m using this stuff from pet store and it doesn’t effect it at all.
I think my ph is too low causing the new growth to be light green , any thoughts?
Indoor grow with Coast of Maine soil, just started adding Jacks321 2 weeks ago. Temps 77, humidity 65%. Lights at about 600-800 ppfd.
7 Likes
First, I would use products designed for cannabis, and a slurry rest will tell you where your medium is at.
9 Likes
Products for aquariums are too weak.
Lime takes too long to degrade to change pH, but it can help stabilize it.
Nutrients are salts with a low pH. Are you pH adjusting your feeds? You shouldn’t be having problems if using Coast of Main and Jacks.
13 Likes
I’m just using distilled water when I mix my Jacks per instructions (1/week) but use my fridge filtered water that’s usually mid 6 ph. I actually just ordered a new apera pH meter. I seem to always have this problem to varying extents. Maybe start adjusting the Jacks water cause it was low 5 ph after mixing?
6 Likes
You can’t use distilled without adding bicarbonate to it, it makes it impossible to ph properly. Add cal mag to your water to get to at least 150 ppm and then you will be able to ph properly. Without bicarbonate, your meter will just steadily drop and not lock in on a reading.
7 Likes
So basically “baking soda” will work? Just ordered the ph up, hating have to wait till Thursday!
4 Likes
It will work temporarily, its effects are short lived, but should be fine til then.
4 Likes
I also run jacks 321, I mix 10 gallons at a time and it’s surprising how much ph up I use to get into the 6.5 area.
I feel your pain with the low ph issues. Mine recently tanked, runoff was coming out low 5’s. Took over 100 gallons flushing 5 plants to get them out of lockout. Good luck man.
6 Likes
This is what you should be doing. It doesn’t make any difference what you start with as the ph will move once you start mixing your inputs. Once the final solution is mixed you should be able to accurately read with a reasonable ph tester. Using jacks 321 recipe in distilled or ro water is typical to be low 5’s just like you’re seeing. The general hydroponic ph up shown above should work better than aquarium asjuster. I think it takes me about .5ml per gallon of mixed nutrient solution to get to a ph of 5.8. Just use something like pipette dropper to add a little then stir well and test. It won’t take much if only adjusting a couple of gallons.
You don’t see the same movement using the filtered water because it likely still has a reasonable amount of minerals in it that buffer the jacks from tanking ph like it does in stripped water. Not a bad thing but worth noting for future reference.
Growdoc’s note about the distilled water isn’t limited to just bicarbonate either. The issue with distilled water doesn’t have any ph so most of our meters won’t accurately display it’s true condition. But anything that will dissolve into water and create conductivity will change this. So it could be bicarbonate, or it could be something like your jacks or even calmag.
8 Likes
Thanks so much for that info. 
Once I get this part of growing down I should be golden! The Jacks video mentions nothing about this. I’m starting to see a light outta this mess. This batch may be compromised as I’m going on vaca and the people staying at the house has no idea what to do. We’ll see 
3 Likes
Sorry but should I add bicarbonate before nutes then adjust pH?
4 Likes
PH should be your final adjustment after mixing nutes.
6 Likes
Something I see a lot is improper care and storage of PH meters. The meters HAVE to be stored in storage solution to prevent the wet bulb from drying out and cracking. Calibration using proper solutions. Periodic validation of calibration.
As stated above you cannot accurately read PH from low TDS water as there is little to no potential hydrogen present. You’ll just get spurious readings.
Doing a slurry test to determine the native PH of your media is probably a good idea.
5 Likes
This right here is correct.
Also great advice!
7 Likes
Thank you so much, I’ve been fighting these conditions off and on for several years now. Always wondering why, thinking I had ph correct. Got this Apera, not the most expensive but hopefully better than my old vivosun crap. Off by 3-4 when it just tested it
4 Likes
have to let your mix sit 30 minutes or so to get a proper reading as it settles out. Then adjust and go in. The light color can be a little N lock or another nutrient out of the ph range. Runoff test will show where that is but I believe a test in between feedings will give a better average of where she stays. Just my thoughts.
2 Likes
Just realized with my new meter, the filtered water I gave them was running over 8ph. I guess that’ll hurt too! Them girls didn’t know what to think. Lol
Probably should just use that water with the jacks and it’ll be close to 6.5, maybe?
3 Likes
I bet if you mix a feed and walk away for an hour you will see the water stabilize. Try it. That ph reading will be the correct 1.
3 Likes
Who’s got time for that? lol
This is a bit harder than I was led to believe “it’s just a weed”.
Thanks for all and any help to come. Definitely always learning. Sometimes relearning 
4 Likes
GH products will stabilize to 6.5 in 30 minutes from 8.5, my water, and hold. Many nutrient lines will settle in at close to optimal. Just have to wait for a clean ,full mix in the solution. Going in blind with these kind of nutrient feeds can be problematic. if you test right after mix, adjust to that, when it settles out you will be off. Adjusting to a settled mix is much more accurate. I top dress so no ph testing. Soil adjusts itself for me. just water.
2 Likes