Girl scout cookies extreme hydro pH level

Hello everyone, thanks for taking the time to read this over. I’m a first time poster here in the forum, or any forum for that matter :). But long time grower.

Here’s the issue, started vegging the gscx last month, have clones going this month…in both runs the plants are showing what looks like calmag deficiencies…however my pH averages around 5.8. My other strains do much better, more prolific growth and size compared to this strain. I have a feeling this strain likes the pH at 6 or 6.1

My question is if anyone has any experience with this strain in a hydro setup and if so have you had this issue and at what pH level do you run?

Thanks in advance for sharing

In hydro I like to run a ph of 6.0 to 6.5 in vegg.and gradually move downward during flowering… :wink:
Each plant has it’s own sweet spot…


Welcome to the forum!

I see peachfuzz is posting, he’s a great hydro grower so I will defer to him. I was just thinking that maybe your ph is fine and you’re indeed lacking a little calcium or nitrogen? Had me wondering what you’re using for nutrients, mixture ratio, and ppm?


Thanks peach, that’s kind of the direction I was thinking of going. Seems cal and mag are more available above 6 according to all the charts…not sure where the sweetspot is for nitrogen tho

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Thanks dbrn :slight_smile:

I’m using the floranova series. Usually start off at 20% recommended levels and gradually work up through veg. Never really get over 40% by week 5 veg on my other strains.
Week 3 I think I was barely pushing 30% strength when I first noticed the deficiencies.
Maybe the gscx is a heavy veg feeder?

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I’ve never used it, but that sounds like pretty low concentration. I’ve also heard of hydro growers allowing their solution to drift a little to help cover uptake ranges.

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Week 2 ppm was around 450-500
Week 3 ppm now around 750
I always do the full strength calmag at 5 ml/g…just the base nutes I cut down in strength

When I first do a rez change I bring the pH down to 5.6 and after a day or two it drifts up to 6.4 or so. But after that I’ve always stabilized it at 5.8 until the next rez change a week later.


GSC-X in my experience is a bit of a twitchy strain. I always get light bleaching in later flower when others are digging the light levels, which could indicate a need for a higher TDS. I would not see anything above about 900 ppm at peak veg. Maybe 1,100 ppm in flower. My sweet spot is 6.0 for almost everything.

Are you doing Lucas or following a feed chart for GH?

Pictures in natural light?

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Thanks for sharing my friend :slight_smile:
I’m going to run her at 6-6.2 for the next week and see how they like it then.

No, just using the normal GH feed chart for recirculating systems.
I’ll have to get pics up maybe later today or tomorrow. Thanks again


The girls on the table, compared to my girls in the pots. Both are three weeks in veg. Just the potted ones more healthy and vibrant. Hydro ones struggling, maybe even stunted


What’s your full nutrient regimen? Everything including hydroguard? Rez temps?

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Did the lights just come on when you took those pics…?
Ph should be around 5.9 to 6.5 in vegg in hydro… at least that’s where I like to drift and I run rdwc with no media…
Don’t look like you have much head room , when you plan on going 12/12 …?
Also , what kind of lights are you running…?
Also , welcome to ilgm…:wink:

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Yep, lights just turned on, a little droopy still.
They’re adjustable, still plenty of headroom if needed.
They’re led lights, 6500 cool kelvin light. I built them together to give me about 500 watts per table. They’ve worked beautifully for me for the last year.

Planning on going to flower in 2 weeks hopefully. Hopefully. If all is well. :grimacing:
I set the pH at 6.3 just now. Will let it drift down a lil over the next few days.
And thankyou!

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I’m using and following the GH floranova series. I follow their recommended schedule for recirculating systems. At 35% strength now, ppms at 750.
I brew an ewc tea for bennies, using orca and ewc with a little mollases.
Which today I just stopped and dumped some 34% peroxide. Rez temps were at 76…and I hadn’t seen much slime but thinking maybe its an oxygen problem as well. So I’m going to see if the h2o2 will make a difference.
Also running co2, and they system is drain and flood coming on every 3 hours for 15 mins.

Room temp never gets over 77, rh at 65% with lights on, 80% lights off

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Probably smart to discontinue molasses into RDWC. That can cause problems. Rez temps are high enough I’d worry about it. I would also suggest running something like Hydroguard.

Well come to think of it I didn’t have these issues before I started brewing the tea. Before that I didn’t use the hydroguard, just the liquid Great Orca and always seemed OK.
But I can’t imagine the molasses being that big of a problem. I’m using maybe a tablespoon or two in a 200 gallon rez. Would think its diluted enough to feed the bennies.
But yea, regardless that’s why I want to see what kind of effect h2o2 has. Maybe the extra oxygen will help the nutrient uptake as well.
Thanks for your help myfriend :slight_smile:
Oh, and I just added a 2nd air pump to the rez. 2 pumps totalling 400 LPM of air