Seedlings Over watered? Heat stress?

[DEA Raider]

1) Growing indoor
2) Watering schedule: Was initially watering about twice a day. At first I tried keeping the bottom of the cube wet most of the day but in hindsight the water traveled up much of the cube. It was not always wet, at times it would get bone dry but I had read that can make the seedling day very quickly so I haven't let it happen much.
- PH 5.8 but was a little higher when i first started watering, maybe up to 6.3
3) Growing Medium: Rockwool for now - PH soaked but I feel that they may still have been alkaline
4) What stage of growth: Seedling ~ 10 days old
5) room temp: One of my biggest early problems, seedlings were getting 75-84 degrees; however, they are hanging at around 77-78 now.
6) Gave them a quick first feeding of around 50 ppm solution the night before the pics were taken, I noticed some yellowing of the cotyledons after so I will bring nutes down a bit (transferring to DWC tomorrow)
7) Light: 600w HPS usually at 100 percent, if it gets too hot in the room I run it at 75 and adjust light accordingly
- Plants were getting around 25k-30k lux for first week but I am experimenting and giving them about 45k-60k lux now
What do you guys think the explanation of the leaves curling under/yellowing is? Most of the seedlings seem to have stunted growth, one was completely stunted and its first two leaves after the cotyledons have turned brownish and dried up, none of the others have displayed what it has. Thanks ! Could really use some insight.

 

[deadgro]

I'd say a combination of over watering and too much heat/light. Let the cubes dry out in between waterings, roots need air. Put up CFLs or get the hps farther away. Seedlings like lower temps in my experience, 70-75f and don't require much light until they have a few sets of leaves.

 

[DEA Raider]

I'd say a combination of over watering and too much heat/light. Let the cubes dry out in between waterings, roots need air. Put up CFLs or get the hps farther away. Seedlings like lower temps in my experience, 70-75f and don't require much light until they have a few sets of leaves.

Thanks for the reply dead. How long should I let the cubes be dry for? I starting moving the light closer because I was noticing a quite stretchy stalk but I could be wrong in my diagnosis there

 

[personal lux]

Thanks for the reply dead. How long should I let the cubes be dry for? I starting moving the light closer because I was noticing a quite stretchy stalk but I could be wrong in my diagnosis there

Over watering and heat stress. Pick the cubes up after you water them to see how heavy they are. but you should pay attention to the dry weight of the cube first off.

 

[DEA Raider]

Over watering and heat stress. Pick the cubes up after you water them to see how heavy they are. but you should pay attention to the dry weight of the cube first off.

How heavy are u suggesting they be?

 

[personal lux]

How heavy are u suggesting they be?

Well here for instance, i water my 16oz solo cup clones with 1 cup of water. Then again when they lose most of the added weight.

 

[DEA Raider]

I let them get very dry last night, watered this morning and they are looking worse than yesterday. I feel that if I dont save them by today 3 of them will die. Could this be a root problem? not getting enough oxygen?

 

[deadgro]

I let them get very dry last night, watered this morning and they are looking worse than yesterday. I feel that if I dont save them by today 3 of them will die. Could this be a root problem? not getting enough oxygen?

Over watering actually means the roots aren't getting oxygen, its impossible to over water a plant, otherwise hydroponics wouldn't exist.

They may just be infected with something. Cubes could've been contaminated. With higher temps comes the proliferation of fungii and rot. There's not much else you can do.

 

[JohnySmith1]

rockwool needs to be soaked in flushing agent for 24 hours, than for another 24 hours in 5.8 pH'd tap water. keep it on the heat mat for maximum 3 days, under the dome to keep it from drying out.

 

[DEA Raider]

rockwool needs to be soaked in flushing agent for 24 hours, than for another 24 hours in 5.8 pH'd tap water. keep it on the heat mat for maximum 3 days, under the dome to keep it from drying out.

Is the flushing agent necessary? They were soaked in Phed water for over 24 hours

 

[JohnySmith1]

Is the flushing agent necessary? They were soaked in Phed water for over 24 hours

Preferably. Some salts in rockwool are hardly soluble in cold water, you can try to increase solubility by placing the jar with soaked rockwool on the heat mat. Keep on checking for changes in pH, once you notice a change, place the rockwool in the fresh pH'd water. Do this until pH will remain constant for at least 12 hours.

 

[personal lux]

I let them get very dry last night, watered this morning and they are looking worse than yesterday. I feel that if I dont save them by today 3 of them will die. Could this be a root problem? not getting enough oxygen?

try making a bowl of water that you can fully submerge your cubes in. no nutrients just straight up water and h2O2 at the correct %. 3% h202 is about 8-12ml per gallon. This might sort things out, move your light atleast 2-3 feet from yoir plants.

 

[Mean Gene]

During my first grow i germed seeds in paper towels then placed in solo cups on a Shelf in my kitchen. No ligts above just waited until they sprouted. Once they had grown their first set i placed under a 125w cfl and watered every 2-3 days. Mine looked just like yours. Curled under leaves from overwatering. I did not ph water. Just used tap. No nutes. All i did was water less.

Seriously just do less. Its a weed. Its gonna grow just let it happen. Young plants cant handle too much light. They dont need a ton of water. you will learn with experience like i did that let the plant tell you what it needs. i think you will be fine though seems like you have done your research and are eager to treat your babies right. Ill be watching for updates.

 

[KillsPlants]

you shouldn't be giving seedlings nutes till atleast 14th day prolly more like 21 cause u got small plants. Also thought runoff should be around 6.3 to 6.8? keep in mind 2 cfls do get hot even tho they say they don't. increase airflow over the light or plants to stop hot spots easy fix is to lift up your lights until thy can handle a bit more light and or heat, I personally start my 85 watt cfl at 12- 15 inches and set another 150 watts 10-12 don't want them burning ur babies. it's easier to start high and work em down so they dnt get burnt leaves I put my hand under the lights and above the plant and if I feel heat the light goes up more g.l

 

[TEK_OG]

1) Growing indoor
2) Watering schedule: Was initially watering about twice a day. At first I tried keeping the bottom of the cube wet most of the day but in hindsight the water traveled up much of the cube. It was not always wet, at times it would get bone dry but I had read that can make the seedling day very quickly so I haven't let it happen much.
- PH 5.8 but was a little higher when i first started watering, maybe up to 6.3
3) Growing Medium: Rockwool for now - PH soaked but I feel that they may still have been alkaline
4) What stage of growth: Seedling ~ 10 days old
5) room temp: One of my biggest early problems, seedlings were getting 75-84 degrees; however, they are hanging at around 77-78 now.
6) Gave them a quick first feeding of around 50 ppm solution the night before the pics were taken, I noticed some yellowing of the cotyledons after so I will bring nutes down a bit (transferring to DWC tomorrow)
7) Light: 600w HPS usually at 100 percent, if it gets too hot in the room I run it at 75 and adjust light accordingly
- Plants were getting around 25k-30k lux for first week but I am experimenting and giving them about 45k-60k lux now
What do you guys think the explanation of the leaves curling under/yellowing is? Most of the seedlings seem to have stunted growth, one was completely stunted and its first two leaves after the cotyledons have turned brownish and dried up, none of the others have displayed what it has. Thanks ! Could really use some insight.

Feeding nutes 10 days old.. do you see or have a feed a infant food.1 1 2 week old.. if you answer yes ..thats your problem.just water light spray, be tender with the babies week 3 start or so start light nutes. .workup ..side note. Don't. Keep ph @5.8 let it be 5.9 6.0 feed in the ph parameters difrent nutes take up at difrent #s.ss.so what take up P at 5.8 takes more K at 5.9 6. get mi

 

[DEA Raider]

I concluded the death of these plants was caused by Pythium fungus, aka damping off. To anyone that was curious.