Name that deficiency!

I am on my 2nd set of seedlings here. The 1st generation suffered through much of the same. Lots of dead spots on the leaves apparently out of nowhere. I was initially told it was mites, but that was eventually ruled out. So then I was told that it was a magnesium deficiency, due to the dead spots and stunted growth, but I added Cal-Mag and the problem is still persisting.

Most of the 1st generation plants I have are no longer getting the dead spots, but most are not growing (2 months old and still hovering around a foot tall). And all of the new ones are suffering just as the 1st ones did despite my adding H2O2 and the Cal Mag into the mix.

DWC system btw. R/O water. More than enough air being pumped into the water. Using Advanced Nutrients Sensi Grow A & B. along with the Cal Mag. I am religiously adjusting my PH and it is never below 5.6 and never above 6.3. Roots seem to be developed nicely on most of the plants.

PPM on the larger plants (which are 2+ months old) is at 800, PPM on the smaller plants (which are 7 weeks old) is at 600PPM. So I don't think that it's nute burn..

The pics are of the young ones, but keep in mind that they are not THAT young. 7 weeks from seed now. but they have not grown for the past couple weeks(none of them are taller than 6inches). They seem OK for a couple days, but then the leaves start dying. Usually its just brown dead spots that leads to the leaves completely dying, but now I am getting some drooping and yellowing leaves (1st time seeing either the drooping or the yellowing).



I am at a loss.

Opps

4got the pix

Looks like PH to me. Reason I hate hydro...I cant grow anything. Sticking with soil for now.

I have zero experience in hydro but from what I've learned scrolling around reading posts in hydro threads is...
R/O water's pH changes alot easier then regular tap water/non R/O water (probably causing your deficiency)
Roseman's DIY bubbleponic tut has lots of useful info, especially in the answer's thread (it's like 1700 pages though so, hard to find exact info for you to save the hastle).

I check my PH 2 or 3 times a day and adjust whenever necessary. I dont understand how that could possibly be the problem.

First Time Growin said:

I have zero experience in hydro but from what I've learned scrolling around reading posts in hydro threads is...
R/O water's pH changes alot easier then regular tap water/non R/O water (probably causing your deficiency)
Roseman's DIY bubbleponic tut has lots of useful info, especially in the answer's thread (it's like 1700 pages though so, hard to find exact info for you to save the hastle).

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Yeah, I have read a lot from him and many others, but there's still no clear cut answer.

I was using 100% R/O initially, but recently starting mixing in a bit of tap water as well. Someone suggested doing that, but it isn't helping.

Either way, my PH seems to be pretty consistent. I check it all the time, but rarely have to adjust it.

Shit... If your checkin your pH regularly then idunno. I hope someone is able to help you! happy growing

I wish I could tell ya cause it almost looks like what I got going on.

4got 2 mention.. i keep the water temp between 65-68degrees F. I read a couple times that this was a good range.. correct me if i am wrong.

going to allow my PH to go a bit higher now and see if that helps (I read that some things are absorbed better at various PH levels), but it clearly states on the Advanced Nutrients site that 5.6 is optimal and that is where I have kept it (very close to that at all times with very small fluctuations).

bump.. bcuz i simply just cannot afford to sit here and watch em all die.

How often do you feed, and for how long? What is your EC/PPM? Room temp?

Green Calli King said:

How often do you feed, and for how long? What is your EC/PPM? Room temp?

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It's DWC so they have constant access to the nutrients. I change it once a week though.

PPM is 800PPM on the older plants (9-10 weeks old) and 600PPM on the plants shown (which are 7 weeks old).

Room temp is 70-73 and the water temp is 65-68.

Cissy said:

It's DWC so they have constant access to the nutrients. I change it once a week though.

PPM is 800PPM on the older plants (9-10 weeks old) and 600PPM on the plants shown (which are 7 weeks old).

Room temp is 70-73 and the water temp is 65-68.

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one of my friends is having the same trouble...interesting to see what happens and what fixes things up...

good luck!

gonegreen00 said:

one of my friends is having the same trouble...interesting to see what happens and what fixes things up...

good luck!

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Well I will definitely make sure to share any solutions that I eventually figure out on my own (the hard way through trial and error), but I certainly hope someone can come along with some experience and spare me the tough lesson!

Cissy said:

I check my PH 2 or 3 times a day and adjust whenever necessary. I dont understand how that could possibly be the problem.

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HiCissy,

Well it sounds as if you are doing everything correctly! Only issue I can see from reading this is that of what Roseman calls "playing the PH game" ie "chasing" a stable PH by continually adjusting with PH down. I took his advice in allowing the PH to rise gradually to the mid 6 mark before adjusting down because I'm not sure that constant adjustment really helps things? Beyond that I have little idea though.

If things get too bad its worth knowing that you CAN transfer DWC plants into soil, I've done it successfully myself and the colour came right back into them within 24 hours!! Amazed me. Hope it don't come to that though for you.

Sorry I cant be of more help, might be worth a PM to Roseman as he does know his DWC, no doubt about that.

Well, your temps seem spot on, so the only thing I could suggest is lowering that PPM down to about 450-500, some were in there and I'm asuming you have good air stones and air pump? I am by no means a DWC expert, but... That's my two cents. Best of luck to you, do you know the strain? come check out my grow some time. I have a journal up. Got a Diablo x S.A.G.E. that I cant wait to flower.

over watering.

maturesmoker said:

HiCissy,

Well it sounds as if you are doing everything correctly! Only issue I can see from reading this is that of what Roseman calls "playing the PH game" ie "chasing" a stable PH by continually adjusting with PH down. I took his advice in allowing the PH to rise gradually to the mid 6 mark before adjusting down because I'm not sure that constant adjustment really helps things? Beyond that I have little idea though.

If things get too bad its worth knowing that you CAN transfer DWC plants into soil, I've done it successfully myself and the colour came right back into them within 24 hours!! Amazed me. Hope it don't come to that though for you.

Sorry I cant be of more help, might be worth a PM to Roseman as he does know his DWC, no doubt about that.

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Thanks for the advice (and it is great advice), but I have read much of what Roseman has suggested and recall reading exactly what you are referring to. Thing is, my PH has been incredibly stable. I haven't had to make many adjustments. So that rules this possibility out as well.

Right now I don't care what the problem is, no matter how bad it is if i at least knew what it was I could address it.

Green Calli King said:

Well, your temps seem spot on, so the only thing I could suggest is lowering that PPM down to about 450-500, some were in there and I'm asuming you have good air stones and air pump? I am by no means a DWC expert, but... That's my two cents. Best of luck to you, do you know the strain? come check out my grow some time. I have a journal up. Got a Diablo x S.A.G.E. that I cant wait to flower.

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950GPH air pump, plenty of stones, and a crazy amount of bubbles. So that's def not it.

Several strains. And none of them are looking too hot.

I can lower the PPM, but it is not that high and more importantly I just recently raised it (gradually).. problem was there even at a lower PPM...

Only thing I can think of is that the Advanced Nutrients Sensi A & B are simply not enough. Maybe I need all of their bullshit little extras to make it work?

Anyone else ever use JUST the Sensi A & B? Like I said, I include cal-mag, but no other nutrients.

nordowell said:

over watering.

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It's DWC.. is that even possible? lol


thx every1..still drawing blanks though

i think i t could be a lockout

chitownsmoking said:

i think i t could be a lockout

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whats the 1st step I should take in solving that problem? any suggestions?

tx