Cotyledons damaged on arrival

[PokPok]

This is my first grow attempt. I've got a heated propagator set to 28C and 4 T5s over it for lights. I planted some scotch bonnets, reapers, chocolate habaneros, trinidad scorpions and 7 pots on Feb 10th. The first seed germinated on the 7th day. Since then they've been germinating at a constant rate. I've been keeping the dome on all the time and taking it off only for 5 minutes every second day to get some fresh air in. When the first seed germinated I turned the light on. After that point I opened the vents on top a bit and slid the dome slightly to compensate for the heat build up. When the cubes look dry on top, I give them 0.8 EC (with nutrients), 6.5 PH water at 30C.
 
Since yesterday, I started getting some new ones germinating with yellow or damaged cotyledons. Why do you think this is happening? I still have about 50% germination in the box so should I still keep the dome on or does it need to come off?
 

 

 

[mpicante]

I honestly think it isnt anything to worry about.They look fine to me.You'll eventually see all kinds of things with cotyd tri's and quads.Just watch them grow and select(cull) as needed when they put on enough growth.Most importantly have fun.

 

[alkhall]

Cotys will fall off shortly anyway, as long as they split the seedcoat, their job is done.
 
I would keep the dome on until all seeds have germinated.
 
Once the seedlings get a developed set of true leaves, I generally move mine to another tray without a dome.

 

[PokPok]

Got it. Thank you.