First DWC having some issues

[dr.tomb]

So im growing with DWC to start my girls out before i move to a Aeroponics up in the flowering chamber.


Medium: DWC with bubblers in the container, water was filled up to and over the rockwool cubes that i had the seeds started in. The rockwool cubes are sitting on a layer of clay pellets. Roots have started to come out the bottom of the 5" net pots into the water.
Strain: Brains Northern Light Special
Nutes: Jake's Granular Veg (http://www.jakesfertilizer.com/products/granular/)
Lights and Cycle: t5 grow light and 6 CFLs on a 24hr on cycle
PH: 5.6-6
PPM: currently reduced to 350 was at 450
Issue: Droopy leaves and bleached leaves

I started off with no nutes for the first 2 weeks and then about 2 days ago i noticed some bleaching on the ones leaves developing. I figured it was due to the lack of nutes so i mixed up a solution of veg nutes at 1/4-1/2 (450PPM) strength and added them. Maybe the water level was too high, i have since recuced the level to below the rockwool and also have diluted the nutes, awaiting replys to what i should try. the bleaching has not happened on the new leaves that are coming out, but there is a drooping happening... not sure if the bleaching is still an issue or old growth. Also the lower leaves are a little bittle on the one in the first picture (with the bleached leaves), the second plant doesn't look as bad as the first.

If you have any questions, please ask.

Pictures:

 

[chernobe]

What temp is your water? Are you using tap water or ro? Any other nutrients besides the jacks? Humic acid being used?

 

[dr.tomb]

Using Tap water, no other nutes, maybe a squeezed of h202 that i added after the wter was changed.

 

[chernobe]

Whats the water temp? its kind of important. When i did dwc i would use ro water, gh flora series, humic acid , cal mag and kool bloom back then and it worked pretty well. Looking back adding silica wouldnt have hurt either. The water temp was as closs as i could keep it to 65f degrees

 

[Scroga]

You got a fan in there? To me it looks like chemical burn from someones fingers touching the leaves or moisture on leaf with poor air ? Droop could be from this shock or too much water too little dissolved oxygen..?

 

[churchhaze]

"I started off with no nutes for the first 2 weeks and then about 2 days ago i noticed some bleaching on the ones leaves developing."

Why does everyone starve their seedlings? This is DWC. Don't start off with no nutes. Raise the ppm to 800ppm from the very beginning and leave it there throughout veg.

 

[MYOB]

That looks like over fertilization to me.

Seedlings can only uptake what they need. If you only have a few leaves and a small root mass, the plant doesnt require high levels of nutrients. It cant use them. They end up staying in the medium and causing toxic buildups and lockout.

Feed them very lightly. I cant imagine a plant that small needing much. You can count the number of leaves on one hand. Those leaves are necrotic, not "bleached" (chlorotic) which leads me to believe it is over fert.

Also, when you do something wait to see if it works before doind anything else. If you change the nute strength & lower the water level you cant know which move helped the problem.

 

[dr.tomb]

Whats the water temp? its kind of important. When i did dwc i would use ro water, gh flora series, humic acid , cal mag and kool bloom back then and it worked pretty well. Looking back adding silica wouldnt have hurt either. The water temp was as closs as i could keep it to 65f degrees

Water temp was 65F

That looks like over fertilization to me.

Seedlings can only uptake what they need. If you only have a few leaves and a small root mass, the plant doesnt require high levels of nutrients. It cant use them. They end up staying in the medium and causing toxic buildups and lockout.

Feed them very lightly. I cant imagine a plant that small needing much. You can count the number of leaves on one hand. Those leaves are necrotic, not "bleached" (chlorotic) which leads me to believe it is over fert.

Also, when you do something wait to see if it works before doind anything else. If you change the nute strength & lower the water level you cant know which move helped the problem.

Yeah probably making to many changes at one time is counter productive.

You got a fan in there? To me it looks like chemical burn from someones fingers touching the leaves or moisture on leaf with poor air ? Droop could be from this shock or too much water too little dissolved oxygen..?

Yup there is a vortex 6" fan up top pulling air through that chamber into the upper flowing chamber.


[HR][/HR]
Update: Not sure which one fixed the issue, but the new leaf growth looks a lot better. I suspect it was a combo of too much water and the nutes.. Just got back from 2 days away, pH was at 6.03, reajusted to 5.74, also didnt adjust the PPM but they raised a little as well. Just looking at the new growth it does look better. When brings me to the question of; when making changes you only look at the new growth, not the old leaves, Correct?

How do they look now, what do you guys think?

 

[dr.tomb]

What do you guys normally run for PPM for the first month?

 

[topfuel29]

Right on, you don't need max water level, it's good to have your roots out in the air, the bubbler sprays the roots with your nutrient solution.
Keep your system clean, with a H2O2 solution every 7-10 day when you change your nutrient solution.
How long does it take your nutrient solution to rebound past pH 6.2
Tap water (city water) IMO that's 99% of the problem most of the time.

 

[dr.tomb]

hmm i never let it get there.. probably like 3-4days i usually pH down around 6.0