Jack's RO formula

CaliWorthington

Well-Known Member
I got the one kilo bag of this Jack's RO formula. It already has cal mag, and is also supposed to prevent "pH crash." It says to mix 3 grams in 1 gallon of water to achieve 0.92 EC. I did this and it came out to 0.89 EC, so that's good. I put another 2.5 grams in and got 1.5 EC.

The problem is that it's not doing anything to prevent pH crash. The pH is 4.38. I was under the impression that this stuff mixed in RO water gave you a pH of 5.8-6.2. I guess not. It smells weird too. Not like it's gone bad, I just don't like the smell. I would probably return it, but the shipping cost would make that pointless.
 

rkymtnman

Well-Known Member
I got the one kilo bag of this Jack's RO formula. It already has cal mag, and is also supposed to prevent "pH crash." It says to mix 3 grams in 1 gallon of water to achieve 0.92 EC. I did this and it came out to 0.89 EC, so that's good. I put another 2.5 grams in and got 1.5 EC.

The problem is that it's not doing anything to prevent pH crash. The pH is 4.38. I was under the impression that this stuff mixed in RO water gave you a pH of 5.8-6.2. I guess not. It smells weird too. Not like it's gone bad, I just don't like the smell. I would probably return it, but the shipping cost would make that pointless.
i tried the Jack's Tap (i use well water) and i had pH crashes downwards after about 3 days. i emailed them and they sent me a bag of RO to try. no more pH crashes.

i've been using it for a few grows now and love it.
 

Failmore

Well-Known Member
You gotta ph to the correct spot. Then it us supposed to stay in that spot. Jacks is not ph perfect and does not self correct ph. Just holds it where you put it kinda.

Also don't feed according to what they say. The chart for jacks tap says 2.4 ec in veg. I'm at 1ec or so and have no plans of going higher.

I have personally had no issues with jacks tap on city water with ph. I ph little under 6 when I do fresh nutes. Goes up a little. Ph back down then it is stable.
 

CaliWorthington

Well-Known Member
i tried the Jack's Tap (i use well water) and i had pH crashes downwards after about 3 days. i emailed them and they sent me a bag of RO to try. no more pH crashes.

i've been using it for a few grows now and love it.
Well, I'm not sure how to explain the low pH reading I'm getting then. I'll email them with my complaint. If I end up not using it you can have mine.
 

CaliWorthington

Well-Known Member
You gotta ph to the correct spot. Then it us supposed to stay in that spot. Jacks is not ph perfect and does not self correct ph. Just holds it where you put it kinda.

Also don't feed according to what they say. The chart for jacks tap says 2.4 ec in veg. I'm at 1ec or so and have no plans of going higher.

I have personally had no issues with jacks tap on city water with ph. I ph little under 6 when I do fresh nutes. Goes up a little. Ph back down then it is stable.
I see. I usually pre-buffer my RO water with House & Garden pH Osmosis Stabilizer. I've got it down to an art. After I add in my Greenstone Nectar AB base and Cal Mag it's always close to 6.2 pH.

I figured this Jacks still needed buffering, but it wasn't entirely clear, so I wanted to see what it did in pure RO water. I'm not going to use it until next flower run maybe. It's never a good idea to switch nutes midstream. I'll have to see what it does on some fresh clones or seedlings first.
 

rkymtnman

Well-Known Member
I see. I usually pre-buffer my RO water with House & Garden pH Osmosis Stabilizer. I've got it down to an art. After I add in my Greenstone Nectar AB base and Cal Mag it's always close to 6.2 pH.

I figured this Jacks still needed buffering, but it wasn't entirely clear, so I wanted to see what it did in pure RO water. I'm not going to use it until next flower run maybe. It's never a good idea to switch nutes midstream. I'll have to see what it does on some fresh clones or seedlings first.
just to be clear, are you saying that after you mix up a batch with RO, it pH's itself to the low 4s?

what happens if you pH UP it to hydro range? will it stay there or does it want to drop back to low 4s?
 

CaliWorthington

Well-Known Member
just to be clear, are you saying that after you mix up a batch with RO, it pH's itself to the low 4s?

what happens if you pH UP it to hydro range? will it stay there or does it want to drop back to low 4s?
Yes that's the pH after mixing it into pure RO water. I'll try mixing another gallon with pre-buffered water.
 

rkymtnman

Well-Known Member
Yes that's the pH after mixing it into pure RO water. I'll try mixing another gallon with pre-buffered water.
if this helps, when i mix mine up with well, it goes to about 6.5 to 6.8 then i pH down to 6. it will go up again on day 2 to about 6.3 adn then i pH down once more to 6. it stays there until day 7 to 10 when i change the res. i do DTW also so no roots in the res.
 

CaliWorthington

Well-Known Member
if this helps, when i mix mine up with well, it goes to about 6.5 to 6.8 then i pH down to 6. it will go up again on day 2 to about 6.3 adn then i pH down once more to 6. it stays there until day 7 to 10 when i change the res. i do DTW also so no roots in the res.
Man, I'm lazy. I never check the PH once I've mixed it the first time. If I change nutes I should probably do that, though.
 

CaliWorthington

Well-Known Member
I lost the clear rubber storage sleeve for my Hanna meter probe, so I've been leaving the probe in the reservoir. It turns out I am getting pH crash with the Greenstone nutes, it was down to around 5.7. I pH'd it back up to 6.2 and now a day or two later it's crashed again. This is a week or more after mixing, but still not cool.

It's barely a week into flowering, I might try switching to the Jack's RO now. The plants might freak out for a few days, but I bet they'll become healthier after a week without this pH crash. This run is just a pheno hunt so I might as well. The Greenstone nutes are getting kinda old anyway.
 

CaliWorthington

Well-Known Member
1.5ml/gal H&G pH Osmosis Stabilizer x25= 37.5ml
5.5g/gal Jacks RO x25= 137.5g
EC= 1.65
pH= 6.20

I watered a few plants with this and they didn't skip a beat, so I ordered a 25lb bag of Jacks RO. I'm making the switch now. No more rose food style AB liquid with the red nitrogen, this "Blue Juice" seems a lot cleaner. I bet it will produce a cleaner smoke too.
 

Rvd9431

Member
i tried the Jack's Tap (i use well water) and i had pH crashes downwards after about 3 days. i emailed them and they sent me a bag of RO to try. no more pH crashes.

i've been using it for a few grows now and love it.
I'm switching to jacks I think because I fought pH crash mid flower thru harvest with my AN sensi nutes. I have well water so I use RO. After mixing I would have to pH up to about 5.9. 24 hrs later it would be up in 6.3 and I'd pH down to 5.9. next day, low 5s. pH back up again. Next day mid-high 4s.....I sometimes had to add 2ml per bucket of pH up. I went thru a half quart bottle in one grow.
Want to try that formula specifically. I had underwhelming bud sizes and had issues dialing in nutrient strength in flower with AN
 
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CaliWorthington

Well-Known Member
What should the soil Ph be when planting the seeds?
I don't measure soil pH.
So much for this stuff not pH crashing. It went from 6.2 to 6.1 to 6.35 and now down to 4.9. I pH'd it up to 6.5 and watered my plants, whatever.
It's cheap, it's working so far, and I spend less time measuring cups of liquid. But I'll have to keep a pH probe in the reservoir 24/7 to know when to pH up when it crashes 4 days after mixing. I should tell the folks at Jack's.
 

Rvd9431

Member
I don't measure soil pH.
So much for this stuff not pH crashing. It went from 6.2 to 6.1 to 6.35 and now down to 4.9. I pH'd it up to 6.5 and watered my plants, whatever.
It's cheap, it's working so far, and I spend less time measuring cups of liquid. But I'll have to keep a pH probe in the reservoir 24/7 to know when to pH up when it crashes 4 days after mixing. I should tell the folks at Jack's.
I think you misunderstand the pH crash part everyone has to pH their mixture after mixing but crash usually comes 48 hours later for DWC
 

CaliWorthington

Well-Known Member
Got ya. I'm late sorry. Do you aerate or keep res circulating?
No worries. I do circulate the res through a chiller but no air stone. I wasn't constantly monitoring my previous nutes pH, so I'm not sure if it was crashing like this or not. It will be interesting to see where it's at tonight. Like I said, I'll be monitoring the pH of my reservoirs 24/7 from now on. I just hope it hasn't crashed hard again by tonight.
 
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