New To Dwc...need Advice

[hydrozac]

So I'm having some issues...
Little back story: long time entheusiast first time growing in my own. First time trying DWC hydroponics as all my buddies do soil. I'll get into reasons later.
Started 2 THC BOMB Autos
Seeded in the pod took 5 days to have a 1 1/2 sprout. This morning I knocked the shells off the First leafs to allow them to span out. Still just running pure water no nutes at this point. Turn on the light for the first time. Went to work. Come back to death...

1 baby is laying over completely and half the stem is dried up. The other is showing signs of dying stem just under first leaves and they did not span out today...still in a ball.
Did they get fried from the light? Running a mars LED
Flushed the water and start fresh with better water. Added hydroguard and growing nutes. Hoping they come back...one prolly won't but the other one has a chance...what happened?

 

[hydrozac]

Trying to upload pic but having trouble

 

[DrMcSkunkins]

Seedlings should be at least 5 or 6 feet away from an led light.

 

[hydrozac]

I do t have room to put the light .ore than 3ft away. How long until they can handle an LED light? I can throw a cfl in there until then.

 

[hydrozac]

A little over a week into the grow/experiement and I had to pull one plant as it was not going to bounce back. It was still trying to grow but was to far gone to be worth anything.
I decided to concentrate on the one in the photo above but as of yesterday it started to develop the same problem. The stem/trunk of the plant is started to shrink in diameter causing the too of the plant that now has a couple leafs to fall over and lay on the pot. What is causing this? My LED light is as high as it can be in the grow box. About 2 and a half feet away. I flushed the water with new better water and started adding nutes. I did a quarter of suggested feeding and added hydroguard as well. I'm starting to see the roots reach the edge of the pod in the water and they look healthy.
What is going on with my plant?
I will try to post a pic of it so u can see what I'm talking about

 

[hydrozac]

Let's see if the pic uploads

 

[hydrozac]

anybody got any ideas?
I can't seem to find anything with my searches..

 

[DrMcSkunkins]

I would say heat issue if you dont have some sort of ventilation and a hygrometer

 

[hydrozac]

The box has to 4 inch fans that draw air out up near the LED light and a large opening along the bottom back side of enclosure. Id say it moves air decently..with the light on I'm around 80-83 degrees inside the box. With the light off I'm around mid 60s to low 70s. I was finding it hard to keep a good humidity level. It kept dropping to low 40s high 30s with lights on and 70s with lights off.

 

[DrMcSkunkins]

83 is at the top of where you want to be, 75 would be better
Plus with a small box the heat can have pockets that are hotter than what you are reading
I would get another small clip fan to circulate air in the box
Also mid 60s might kill it too, if it drops below 70 and then goes above 80 in one day it can shock your seedling

 

[Jeffino]

That looks like it's wayyyy too wet. You want the roots to have to go searching for the water, if the cube is drenched, they will just rot away. I would also recommend growing your seeds or clones a little bigger before transplanting into your hydro system.

 

[Saint Skinny]

That looks like it's wayyyy too wet. You want the roots to have to go searching for the water, if the cube is drenched, they will just rot away. I would also recommend growing your seeds or clones a little bigger before transplanting into your hydro system.

Spot on, Champ! I think may be dealing with them "damping off" from too much moisture in the puck. The media should be above the waterline, the bubble from the airstone popping at the surface is enough to keep your babys alive, and to tell them "there's water down here... if you want it, reach for it"
This is from Wikipedia:
There are various symptoms associated with damping off; these reflect the variety of different pathogenic organisms which can cause the condition. However all symptoms result in the death of at least some seedlings in any given population.

Groups of seedlings may die in roughly circular patches, the seedlings sometimes having stem lesions at ground level. Stems of seedlings may also become thin and tough ("wire-stem") resulting in reduced seedling vigor. Leaf spotting sometimes accompanies other symptoms, as does a grey mold growth on stems and leaves. Roots sometimes rot completely or back to just discolored stumps.


As for the top turning green, im assuming it's the same thing as with rockwool, it's just kinda there. It may not be a good thing but it happens. Cover your top with panda film and presto! No light, no algae. I'm pretty sure that alot of potted plants have algae on the media surface, but being dark it's harder to see. I just noticed the perlite on the top of my mix (one of the plants w/o gnat nix. GN seems to reflect light and help with the algae) was turning a green tint.

And I'm a believer that the first 30 days of life (from seed, NOT CLONES) should be spent under the light they will be vegging under. Ive sprouted seeds under 1000w of light and they did great! You just have to make sure your baby is far enough that it won't get burned or evaporate all the water off your puck (not really an issue with DWC if done right, more for seedlings in trays with only pucks or 1.5" )

 

[Strasser]

Cover the base of the plant (I use mylar, picture attached). Harmful bacteria thrives where light meets water.

Keep your resevoir water temperature below 70 degrees and add a root inoculant like Hydroguard.

In what way are you oxygenating the water? It looks like lack of dissolved O2 could also be a large contributor. Consider adding another airstone.

Do these things and this issue will resolve.