Seedling deficiency

[nLinks]

Hey, I'm growing a CBD strain and its had some kind of deficiency since the first week of sprouting. First, it's new grown leaves started to curl up, and now it's developing brown patched on the tips/ middle of the leaves. It's also not growing nearly as fast as it should. Does anyone have any ideas what it could be? I'm growing another strain beside it and it is flourishing so I'm not too sure what I'm doing wrong with the one since if doing the same thing for both

 

[LaoWhoo]

This will be good. Thought I had similar issues and will be following. If I'd known better I wouldn't have grown different strains for our first try, but am also learning a lot b/c of the challenges.

 

[Simplicio]

Hey, I'm growing a CBD strain and its had some kind of deficiency since the first week of sprouting. First, it's new grown leaves started to curl up, and now it's developing brown patched on the tips/ middle of the leaves. It's also not growing nearly as fast as it should. Does anyone have any ideas what it could be? I'm growing another strain beside it and it is flourishing so I'm not too sure what I'm doing wrong with the one since if doing the same thing for both

There are a few possibilities:
You accidently spilled liquid on the affected leaves.
The affected plant was over-fed, but since new growth looks good, it survived the force-feedings.
New growth has lighter colored, thinner leaf tips that always look a bit colored, so the leaf tips might not be a problem.

There will be no deficiencies if the correct amount of fertilizer is used with proper pH, but many people harm their plants by over-feeding.
Chasing non-existent deficiencies isn't fun.

 

[7.62]

Looks like a splash of ferts to me.