Nute burn ?

[Cranky]

Hoping it's just nute burn, this is 24 hours after feeding 1ml/l AN Coco Grow A & B, 2 ml Voo Doo, 1ml Calmag , PH at 5.8. 2 weeks old in Coco under 200 watts of cob at 20 inches. There was no sign of it before yesterdays watering.

 

[Mr Green Fingers]

Hoping it's just nute burn, this is 24 hours after feeding 1ml/l AN Coco Grow A & B, 2 ml Voo Doo, 1ml Calmag , PH at 5.8. 2 weeks old in Coco under 200 watts of cob at 20 inches. There was no sign of it before yesterdays watering.View attachment 882268 View attachment 882269

Those cobs are powerful, I would say the lights are frying your baby

 

[bushmasterar15]

When I started mine under cobs I had them at 36" from top of pot.

 

[Cranky]

Thanks for the reply's, I've raised the light so we'll see how it goes. I wondered about the height but where it was just the bottom leaves affected I kind of shrugged it off.

 

[puggle6]

pH should be a bit higher for Coco iirc so possible lock out, maybe a bit under feed and CalMag def.. lock out can show up like that though.

Whats your EC/TDS/PPM? (Just one of them, not all lol)

As said maybe a bit of light bleaching, or heat.. they don't look stretchy so lift those lights up to where the cob guys recommend!

f6

 

[Waira]

-- not nute burn at all! It looks like P defc.,... coco is devoid of nutes... was this the first feeding? How are you running this coco, in reg. pot, or through a feeding system? Are you doing drain-to-waste if in reg. pots? Actually, I should just ask if you're experienced with coco growing, which is way different than true soil growing,... many do's and don't's in coco! pH is OK at 5.8,...
Like F6 mentioned, knowing your EC/ppm's going in and coming out are key thing to monitor,... hand feeding pots should be getting 15-20% run-off each time, and never water alone (can star to screw up the coco's CEC balance)... all that run-off is done to prevent nute salt build-ups.....

 

[puggle6]

P! Yep can see that now!

They do look hungry in general tho!

 

[Cranky]

First time with coco, single plant in an Autopot. This was the third feed, top fed, waiting for more growth to turn on the res. I'm using the Advance Nutrients Coco A&B, Voo Doo and cal mag. I emailed Advanced and was told I shouldn't need the cal mag because it is in the coco a&b.

 

[Mike20132]

First time with coco, single plant in an Autopot. This was the third feed, top fed, waiting for more growth to turn on the res. I'm using the Advance Nutrients Coco A&B, Voo Doo and cal mag. I emailed Advanced and was told I shouldn't need the cal mag because it is in the coco a&b.

With powerful LEDs, you might wind up needing some calmag later on. I guess what I am saying is don't rule it out if you have to troubleshoot leaf issues down the road.

 

[Olde School Player]

All good stuff here already & I agree toward light bleaching. But to be safe, is there any chance there was water on those lower leaves, like maybe the plant was misted? Do you have a circulating fan blowing across the plant? Not only does this prevent condensation & help with excess light heat, but the gentle sway of the breeze acts to strengthen the main trunk of the new baby.
As to the calcium idea, if you are NOT using RO water then AN is probably right. Most "hard" water is that way due to dissolved calcium, & to a bit lesser extent magnesium, in the water supply. Under that scenario the additional cal-mag in your nutes should be enough. But if you're on RO, or the absolute worst - softened water - then the AN bases won't have enough Calcium. 4mL per gallon is a sweet zone (1mL / liter if you're on that side of the pond) for RO. As to calcium deficiency symptoms, that normally shows up as small rust colored spots splattered across the insides of the leaves that have been receiving the most light. In your pic, it looks like only the first true leaves on your plant were affected. So either light bleaching; or a normal N deficiency on the first leaves of the plant as it matures. Those always die off as the plant starts its vertical growth.
Back to my softened water comment - salt (or potassium chloride) based water softeners remove virtually all the calcium and magnesium from hard water, without really lowering the overall ppm of your water. This causes cal-mag deficiencies if not replenished. Then if you DO replenish the Cal-mag in the softened water, your basic water ppm's go so high that it fools you into underfeeding with N-P-K based nutes. You could measure 500-600ppm (500-scale / 1.0 - 1.2 ec) with just your base softened water before any N-P-K is added.
Just my thoughts, hope you find something helpful here.