Proplems with leaves

This is a slight burning from over feeding, not a nitrogen deficiency. A plant that size, in a pot that size and growing in good quaity soil should not need any extra feeding for at least the first 4 weeks. After that time, quarter to half strength fertilizers should be used sparingly, no more than every 7-10 days. A schedule of plain water/plain water/fertilizer/plain water/plain water/fertilizer etc works well.

I think a critical piece of information on your lighting info is missing - distance. Optics as a subset of physics is primarily geometry. Inverse square law applies relative to distance.

Looks like a little bit of burning to me. might want to lighten up the feeds or it could mean the soil is a bit to hot. Best to start a diary so other can follow along.

Hey VikingFloh420, I took a look at your grow, and I would guess it's either a nitrogen or magnesium deficiency. Of course, it's hard to say for sure, but since you've been feeding lightly so far and the issue is starting from the bottom, I’d lean towards a nitrogen deficiency. Best regards!