Leaves shriveling and dying!?

[Sauce]

Here was my 1st problem thread but since then they have recovered by are having other weird problems.

http://www.icmag.com/ic/showthread.php?t=32651

Here's what they look like now:













They are being fed with ~500ppm (.5 conv - 1 EC) PBP Bloom, Tiger Bloom, LK, and fulvic acid about every other watering. The other watering times are just phed water. I am having weird ph problems (rising) which I think are caused by all the hydroton and lava rock. They are 1 month into flower but the right side plants were flowered imaturely which I think is why they are so underdeveloped.

The leaves (bottom 1st) are getting very light yellow/white and the tips brown and eventually shrivel up. The bottom most affected leaves come off with barely any force at all. Also some bottom leaves are a consistent very very light yellow, almost pale. Leaves in the pics are the ones that came off with a very tiny pull, basically no force at all. Some have fallen off naturally.

Anyone know what's wrong with them? I assume ph is part of it but I assume there are some deficiency or toxicity problems.

Thanks
Sauce

 

[MynameStitch]

what nutrients are you using?
how often asre you using them if you are?

those leaves if came from the lower to bottome or middle part of the plant area, they are nitrogen deficienct

i need more information though

and a picture without the hps on
you check the ph run off at all?>
i assume not...

what setup are you using?

hydroton rockwool>?

you got air stones in there?
what is the water temps?

 

[Sauce]

what nutrients are you using?

**Was using FN Grow but now PBP Bloom and Tiger Bloom (last 2 weeks). Additives include Liquid Karma and fulvic acid.

how often asre you using them if you are?

**About twice a week maybe. I water (nutes or water) about every other day, and 1/2 waterings are just water. So roughly every 4 days they get fed, but the pump isn't on a timer so I just water when I think they need it.

those leaves if came from the lower to bottome or middle part of the plant area, they are nitrogen deficienct

**I was thinking N, P, or Fe deficiency but I'm not sure.

and a picture without the hps on

**Will get that later today.

you check the ph run off at all?>
i assume not...

**Yeah it comes off at like 7 (color indicator drops). I ph it between 5-6 before it hits the plants. That's why I think the hydroton and lava rocks could be affecting ph. Like I said, I think ph is part of the problem but I think there are some nute problems as well.

what setup are you using?
hydroton rockwool>?

**2x 4" rw cubes (stacked) for each plant and the roots on the bottom grow out into the hydroton and lava rock mix (mostly hydroton).

you got air stones in there?

**No but I have read in an ebb/flow setup they are not necessary. I don't think it's low dissolved o2.

what is the water temps?

**74* at last check but I don't think it's quite as important in ebb/flow as in DWC, NFT, or something with frequent water contact.

If you need any more info just ask. I always appreciate how helpful you are stich.

Thanks
Sauce

 

[Sauce]

Ok here we go, more pics. These ones are much better:












The lower leaves are shriveling and dying off. Even the top leaf tips are slightly burnt which makes me hesitate from giving them more nutes, however they look hungry, I just don't know.

Also it's hard to tell from the pics, but the 3rd pic of the lightly colored leaf has pale veins with like green/yellow between the veins.

 

[SDBX2]

Yeah I'd like to know this - I have this problem too - I use NFT and Canna Aqua and never seemed to get the problem before switching to aqua. Perhaps I'm gonna change nutrients.

It's either burn or deficiency, but I'm buggered whether I can work it out.

 

[m.steelers]

That's a def for sure. I would say some N because of the uniform yellowing on the lower leaves and eventually they do dry up like that. Also, it looks like some of those middle yellow leaves are showing P or K def. The runoff ph should be lower to get that P or K. I would say the ph is the main culprit. and maybe your ppm should be wee tad higher for those size plants.

 

[MynameStitch]

you have a nitrogen problem going 100%
are those roots sitting in water ?? or is it like ebb and flow where it just drips at certin times?

low dissolved o2 levels will cause nitrogen problems.......

did you wash your lavarocks out real good before using them?

your system ius so messed up, its like hydro and kinda something else.......

you cant have your roots growing in lava rocks...... lavarocks is really supossed to be a medium on not a growing medium,. a medium that holes the plants in place

what made you grow your plants like this?

 

[Sauce]

Lol I am high right now so that made me laugh.

you have a nitrogen problem going 100%
are those roots sitting in water ?? or is it like ebb and flow where it just drips at certin times?

Like I said, every other day it gets a watering. The pump goes on until the table is flooded (overflow excess) and a regulator valve allows the water to drain back into the res in about 10min. N is what I most suspected but I think maybe P and Fe (?) too.

low dissolved o2 levels will cause nitrogen problems.......

I will add a air pump to the res but honestly I don't think it makes a difference. I ran it with a pump for a little bit and didn't see much difference. I got about the same consensus when I searched on it.

did you wash your lavarocks out real good before using them?

I washed them for awhile in my yard with a hose but it stills seems like they are giving out some kind of salt deposit. Same goes with the hydroton to a lesser extent. I think possibly part of ph the issue.

your system ius so messed up, its like hydro and kinda something else.......

It's just ebb/flow but the rocks are there for moisture to remain where the excess roots grew out of the cubes. I can't stack rockwool really high in such a vertically confined space. Without the rocks the roots on the bottom died.

you cant have your roots growing in lava rocks...... lavarocks is really supossed to be a medium on not a growing medium,. a medium that holes the plants in place

Most of the roots are in rockwool. The excess roots grow out into the hydroton with some lava rocks. Here's a pic:

what made you grow your plants like this?

Don't know lol. I don't like ebb/flow and plan to switch back to DWC or possibly a drip/NFT setup for next round.

Thanks for the replies
Sauce

 

[MynameStitch]

ok, no adding a air pump wont fix the problem, i was just letting you know for future reference that low o2 levels causes nitrogen problems

not saying thats whats wrong with this situation, the situation here is you just need to give it some more nitrogen,

something that has god amount of nitrogen,

which nutrients are you using now? and how often?

 

[SDBX2]

Would it help to give them veg nutrients for a while, which seem higher in nitrogen?

Like I say I also have this problem 6 weeks into flowering (a 9-10 week variety) and couldn't decide whether it was burn or N deficiency. I've now got them on well ph'd low nutrient solution for a bit to try and even them out a bit, but they're still yellowing. I've got P-K in there as well, which I suppose lowers the N even more does it?

I've once been told that using the veg version of the nutrients - I'm using Canna Aqua, for the first week or couple of weeks into flowering helps preserve the N. Is this correct?

 

[MynameStitch]

did you switch to bloom nutrients right when you switched over to 12/12?

if you did then thats one of the reasons why you have this problem.........

plants just dont switch over to lowering mode over night and therefore do not require bloom nutrients over night, they still need veg nutrients for the first week for indica dominant strains and 2 weeks for sativa based dominant strains


and using the veg nutrient will fix the problem, as long as that nutrient doesnt have a high level of P AND K you can mix it with your bloom fert too but use half as much as they tell you to on the back after you fix the problem'

tyou dont waqnt to add ti much nitrogen otherwise you will slow down flowering

so what you need to do now is use what you normally would, the amount you did in veg and give it one good dose for now

then next time you feed dont gvive it the veg but give it the bloom'

then after that feeding you can use the veg nutrients from then on with the bloom but use half as much as you would normally

do you get what i mean?

 

[Sauce]

Yeah somewhat.

I actually did give it grow ferts (FloraNova grow) about 2 weeks into the start of flower. I just switched about 2 weeks ago to a combo of PBP Bloom and Tiger Bloom.

I just fed them today but next feeding I will give them some grow nutes again. I will feed them more often too.

Thanks for the help.