Please help me figure out what's going wrong with my seedling

white spots on the tips of the first leaves, new growth has yellowed mottling. In rock wool cube, watered the surrounding cubes with go box nuts at 1/2 the dilution per the box. What is going on here?

Could be a mag def, I've heard of that happening to seedlings from overwatering. Looks kinda like it, yellowing can be normal for new growth on a seedling. Should darken alittle once it matures more

Thank you. I think you are right on about the yellowing. I took that pic last night, and today the yellowing is all gone. I love this little plant, it is growing so fast. i swear it doubles in size every day LOL

I'm still a little worried about those spots on the lower leaves. I'll watch my watering more carefully and add a little more cal mag on the next go around and see if that helps.

Thanks again.

Are you going to soil or hydro? I wouldn't add very much nutes, they are very sensitive. It will grow really quick, I wouldn't worry about it too much. Another thing, roots really like the dark, it looks like your containor is clear, maybe wrap something around it so the roots are in the dark

Hydro. I will be popping it into the DWC system later today