Magnesium Deficiency or something else?

[Billy the Mountain]

Technically, we're not hydro...it's Promix soil but I'm using a drip system. At best it's a 'hybrid system' that does a constant drip for soil settings. The system uses osmotic pressure to open and close valves for drippers if the soil dries down enough so it's not dripping or flooding on a schedule but just keeping soil at a constant moisture level range.

Yeah, while technically it's a "soilless medium", it's generally treated like hydoponics
pH should be around 6 w/ promix

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[Roger A. Shrubber]

they use dolomite lime in peat moss to raise the ph, but it gets used up, so the ph of the peat will eventually start to drop. you can add more lime, but it takes a while for it to dissolve and become available. so maybe ph 3 or 4 points higher for a couple of weeks, like around 6.5 or 6.6, and then check the ph of the medium, using a slurry test. if it's below 5.8, maybe add a little more lime.
next grow, top dress with some lime when you put them into flower.

and i changed to coco coir about a year and a half ago, it's a much more forgiving medium, once you learn its tricks

 

[LeastExpectedGrower]

they use dolomite lime in peat moss to raise the ph, but it gets used up, so the ph of the peat will eventually start to drop. you can add more lime, but it takes a while for it to dissolve and become available. so maybe ph 3 or 4 points higher for a couple of weeks, like around 6.5 or 6.6, and then check the ph of the medium, using a slurry test. if it's below 5.8, maybe add a little more lime.
next grow, top dress with some lime when you put them into flower.

and i changed to coco coir about a year and a half ago, it's a much more forgiving medium, once you learn its tricks

Thank you. I appreciate it. I'd been doing fine with it, just treating it as soil (though I always pH a little low for soil anyway). I'm using Blumats right now, but that's just for 'time away' travel and am 90% sure I'll be hand-watering when I'm not traveling. I'll slurry test it once I'm back from being on the road and see where we are. I'm currently on week 6 of veg. In the meantime, I'll keep with the foliar spray and aim my pH south a bit more.

 

[LeastExpectedGrower]

Ok, went down and adjusted my reservoir pH downward to about 6. I'll keep an eye on it drifting upwards.

Let's see if that, plus a foliar feeding sorts things out.

 

[Bukvičák]

It is not so long ago when I have started growing, I have read a lot (as many others) but havent had the succes I wanted, I have join RIU and saw struggling people the same shit I did. I have immediatelly realized that 90% of things I have read are total bullshit and advices given are only parroting the net. I have focused on scientific articles, but at first I had to figure out what the fuck the basic is. If I was following what other said, I would not be probably growing anymore now. During that time I have gained exps and I am not choking on those yellowed droppy leaves or whatever else third week of flower or even worse in veg phase anymore. I am proud to say that my product is better than any other shit bought in coffee in whole fucking country. So if I am saying you do not need pH down than you do not need it, but you can figure it out by yourself few years later. I am not master G, but when I give some insight, than it is not based on dumb network copy and paste, but on my own grow. Hopefully you will figure it out before you flip. Good luck dude!

 

[LeastExpectedGrower]

It is not so long ago when I have started growing, I have read a lot (as many others) but havent had the succes I wanted, I have join RIU and saw struggling people the same shit I did. I have immediatelly realized that 90% of things I have read are total bullshit and advices given are only parroting the net. I have focused on scientific articles, but at first I had to figure out what the fuck the basic is. If I was following what other said, I would not be probably growing anymore now. During that time I have gained exps and I am not choking on those yellowed droppy leaves or whatever else third week of flower or even worse in veg phase anymore. I am proud to say that my product is better than any other shit bought in coffee in whole fucking country. So if I am saying you do not need pH down than you do not need it, but you can figure it out by yourself few years later. I am not master G, but when I give some insight, than it is not based on dumb network copy and paste, but on my own grow. Hopefully you will figure it out before you flip. Good luck dude!

Thanks! Either way, since I've just sprayed with foliar Ca/Mg if it's either, I should have them covered. I've done pretty well so far, not flawless, but each grow gets better and better. I too had trouble previously about 3rd week of flower, but I assume it was related to not adjusting my feed quickly enough and being caught out with not enough P/K. I always figure we're asking a plant to act 'unnaturally' in that most of us are growing indoors under lights and taking care of the nutrient needs in a non-natural construct kind of way, so it's gonna be a challenge, especially since we're asking the plants to produce more heavily than they want to in nature, etc.

 

[Roger A. Shrubber]

Ok, went down and adjusted my reservoir pH downward to about 6. I'll keep an eye on it drifting upwards.

Let's see if that, plus a foliar feeding sorts things out.

the peat running out of lime will LOWER the ph, you want to raise it...

 

[Billy the Mountain]

the peat running out of lime will LOWER the ph...

That's exactly why peat sucks imho.
A medium without stable pH is an uphill battle.
Coco is a better choice

 

[LeastExpectedGrower]

the peat running out of lime will LOWER the ph, you want to raise it...

I'll know shortly...I just grabbed a sample from my sleeping plants and currently have it soaking with some filtered water that read exactly 7pH with my Bluelab meter.

 

[Billy the Mountain]

I'll know shortly...I just grabbed a sample from my sleeping plants and currently have it soaking with some filtered water that read exactly 7pH with my Bluelab meter.

By "filtered" I hope you mean RO, otherwise use distilled water

Slight tangent:
A pH pen won't work reliably on distilled or RO water, there's no H+/OH- balance to measure

 

[LeastExpectedGrower]

By "filtered" I hope you mean RO, otherwise use distilled water

Slight tangent:
A pH pen won't work reliably on distilled or RO water, there's no H+/OH- balance to measure

Unfortunately I'm out of distilled water right now. I ran it through my ZeroWater filter and it has a measured PPM of 0 and a pH of 0. Which is actually way closer to neutral than any distilled water I've been able to buy (usually measures a bit acidic when I've bought it).

After a half hour soak in 7pH 0ppm water the pH reads 6.4

 

[Roger A. Shrubber]

Unfortunately I'm out of distilled water right now. I ran it through my ZeroWater filter and it has a measured PPM of 0 and a pH of 0. Which is actually way closer to neutral than any distilled water I've been able to buy (usually measures a bit acidic when I've bought it).

After a half hour soak in 7pH 0ppm water the pH reads 6.4

hmm. let me consider that for a while....

 

[Billy the Mountain]

Unfortunately I'm out of distilled water right now. I ran it through my ZeroWater filter and it has a measured PPM of 0 and a pH of 0. Which is actually way closer to neutral than any distilled water I've been able to buy (usually measures a bit acidic when I've bought it).

Distilled water is always pH 7 by default, H+ to OH- is 1:1 (or 0:0 with distilled)
A pH meter needs some ions present to function, which aren't present in 0 ppm water

 

[LeastExpectedGrower]

hmm. let me consider that for a while....

Theoretically, it seems like that should be a good place to be, but then, I'm the one having the deficiency problem.

 

[LeastExpectedGrower]

Distilled water is always pH 7 by default, H+ to OH- is 1:1 (or 0:0 with distilled)
A pH meter needs some ions present to function, which aren't present in 0 ppm water

Tell that to the folks in the store when I buy it... For me it always reads down in the mid 6's. Which is probably from it having contact with air along the way.

 

[Bukvičák]

Thanks! Either way, since I've just sprayed with foliar Ca/Mg if it's either, I should have them covered. I've done pretty well so far, not flawless, but each grow gets better and better. I too had trouble previously about 3rd week of flower, but I assume it was related to not adjusting my feed quickly enough and being caught out with not enough P/K. I always figure we're asking a plant to act 'unnaturally' in that most of us are growing indoors under lights and taking care of the nutrient needs in a non-natural construct kind of way, so it's gonna be a challenge, especially since we're asking the plants to produce more heavily than they want to in nature, etc.

I am not a fan of spraying plants with anything, but whatever works for you dude… have fun and good luck!

 

[PJ Diaz]

I am not a fan of spraying plants with anything

Why not?

 

[Roger A. Shrubber]

i'm not familiar with the formula of maxi products. i use Jack's 3-2-1. half strength for veg, full strength for flower. i mix up a jug of 200 ppm MKP and add 200 ml of that every three days for the first three weeks of flower. i have a jug of sul-po-mag mixed up at 150 ppm, and give them 200 ml of that every other day when they start to swell, maybe 3 times total...and shit stays healthy and green till the end. when i was using premixed shit i hadi trouble all the time, and it was stupidly expensive and complicated.
all i can recommend is trying to replicate the ratio of 3-2-1 with the products you're using

 

[Bukvičák]

Why not?

I do not consider it necessary, too much work and so on…

 

[PJ Diaz]

I do not consider it necessary, too much work and so on…

Of course it's not necessary, but it may still create improvements. Spraying a plant with a foliar feed is a lot of work?