Yellowing Growth on Young Seedlings

[SweetLeafGrow]

I'm noticing an issue with a couple of seedling from my Brothers Grimm/Ace Seeds grow and wanted to put it out there in case there is anything I should be doing for these two plants. I know slightly yellow on new growth is normal but this seems to me to be a bit extreme.

The first one, Cinderella XX by Brothers Grimm has been very weak and slow from sprout. It popped and then just sat right on top of the soil. I carefully dug out a bit of soil around the plant to keep it from sitting right on top of the soil. If finally did shoot up a bit but the tips of the cotyledons were a bit burnt and brown on the tips, still are. The growth has been very anemic and what little there is, is a very yellow color like it's lacking something.

The second, not quite as severe, is the Rosetta Stone by Brothers Grimm. She has been doing well but has some of that same yellowing going on, which seems to be slowly replaced with good green color from the tips of the leaves toward the center. I also noticed a bit of leaf twist on both of these plants in the first couple sets of leaves after the cotyledons.

I am using a MarsHydro TSW 2000 set @ 25%, 24" from the tops of the plants. Growing in Roots Organics Lush soil, no feedings yet. Just transplanted and watered in one week ago, watered once since when the pots were light. Temps ~75F daytime, around 68F at night, RH 40-60%.

One thing of note that might be important, I got this soil, that is supposed to be pretty good, but when I got it, it had a hole in the bag and was very, very dry. Should I be conditioning the soil before I get a plant in it in any way when it's so dry like that?

Here is a group photo, China Yunnan from Ace in the back row.

Cinderella XX

Rosetta Stone XX

 

[steamroller]

I wouldn't worry .
Just give them the time they need when young.
When do you plan to start feeding ?

 

[Chem77]

60’s is on the cold side for young seedlings. My basement is in the 60’s and I like to use a heat mat for a few weeks. It helps with drying out the dirt a little faster also. LED’s don’t produce much heat like fluorescent or hids.

 

[SweetLeafGrow]

I wouldn't worry .
Just give them the time they need when young.
When do you plan to start feeding ?

Thanks Bro, just never seen such anemic growth in a seedling such as I am having with the Cinderella. This morning she is still almost white with the new shoots coming out. I am assuming I won't need to feed till almost time to flower as they will go in 3 gal pots when they are ready, which should last them a week or two past transplant the way I figure.

60’s is on the cold side for young seedlings. My basement is in the 60’s and I like to use a heat mat for a few weeks.

I agree Bro, and I thought this could be some of the cause, thank you. I'm trying to keep temps down at night for the flowering tent while at the same time keeping this tent a bit warmer. Yesterday I installed the LED light ballast inside the tent as I had them separated to reduce the heat inside the tent during the summer months. I also opened up one of the lower flaps in the tent and put a small space heater throwing a bit of heat toward the intake. It worked and kept temps around 72 all night last night during lights off (18/6 light schedule). I did use a heat mat in the beginning but I think they are past that point once they were put into the 1 gal pots.