Seedling heat stress?

I have a Seedling, it's about a week old. It has a problem which I think is heat stress, or deficiency.

The FACTS:

-7 day old seedling
-3" away from a 4' 4 bulb t5
-Sitting in soiless medium, used by green houses.
-Very carefully watered when soil is light and dry to touch.
-24/0 until last night I went to 18/6
-Infrared temp check of plant leaves several days ago was 80°.
-No nutes used as of yet, but a line up of green planet is avail to use.
-Last check of water ph was 6.8, but the water I have been using has been sitting out for several days.

The pic is yesterday, the light browning around the edge has gotten worse and there is a downward curl to the leaves.

I also lightly watered it yesterday as it had been 3 days since I watered it and it was dry.

Heat stress curls leaf tips and edges upward. Surprisingly green for no nutes.

I didn't have my phone on me when I checked it this morning or I would have taken a pic, it was much worse and the leaves were curling down. I'm hoping it fixes itself, but if it doesn't, should I use a quarter strength nute solution.

No nutes in your medium? Yes, feed them

Nutes already in your medium? Figure out if they were overfed or not. If leaves are turning down sharply at point, like claw, that is a sign of overfeeding. If entire leaf is going limp that is a sign they need to eat.

There might be some small amount of organic nutes in it. It's 7 days from seeds, isn't it too early?

Bomixius said:

There might be some small amount of organic nutes in it. It's 7 days from seeds, isn't it too early?

Click to expand...

It all depends on how much nutes are in your medium and how much you are planning on feeding it. They normally don't need much for first two weeks but yours look pretty good sized for 1 week up. If the plant is calling for food there is no reason to stick to a schedule. Any feedings would need to be light for sure.

Try to take a pic later from some angle other than straight down so we can see the leaf color and structure and figure out what she wants. She will want cal/mag in her water for sure so that is something you could also comment on. What is your water quality?

Will do, will he a cpl hours, maybe when I get home it will be good news.

Well I have the bag at home, and will post a pic, its light on nutes, but this girl is growing well. I'm thinking of going to pro mix when I go up to the 3 gallon pot. It's easy to get around here, and not many other specialty soils are, unless I make my own.

The npk of the medium is
0.09-0.06-0.10.

• Mix of sphagnum peat moss, dolomitic limestone, natural wetting agent and starter charge

TThis was 1 hour ago. It was warm in the room. The fan was directly on the little one.

It's not heat stress from a T-5 flouro, you can keep those bitches right on top of your plants and they just love it. That soil looks like crap. Therein lies your problem.

She doesn't look hungry to me, I would stay with water only for another week. Keep an eye on the new leaves, if they stay straight you are in good shape. I would try to get a ph reading on your medium to make sure it isn't too low.