Curled leaf tips lower leafs yellowing

My plant is 4wks in veg indoors 18/6 light cycle ,soil organic grow.
The leaves started to curl at the tips 2wks ago i checked the ph runoff it’s 6.5 and the water being used to water the plant is 6.5. No idea what’s causing this if anyone could enlighten me happened to my last grow too.

Bump

What strains are you growing there? They look very Sativa like and I’m wondering if you are feeding it too much Nitrogen. I usually water my tent girl all the same but some thrive and some did meh on the same feed. I currently have 2 landrace Sativas in my tent (Ace Seeds Golden Tiger & Killer A5 Haze) and they are only being fed PK Booster and Cal/Mag nutrient wise. I was using a sip of fish shit/seaweed feed for everyone at the start but G.Tiger was too green and my tips were starting to go white. Switched my feed and the tips haven’t gotten worse and plant looks healthy. Some yellow leaves here and there but probably because lack of light penetration and almost 5 weeks of flowering. So I sort of expected to see them on my plant at this late stage in the grow (Day 89 from seed)

I’m growing 2 Thai landrace. The signs started to show at 2wks veg. I’ll try ease off the N fertilizer for now. Thanks for the reply

My Golden Tiger is very Thai like in its leaf growth. So yeah, I would think if you stop the N feed you’ll see a difference. The tips won’t improve but your problems should ease up I would think. Here’s my gal from yesterday. Top down view you can see where the N was hurting her and stopped giving her N probably around week 4-5 in veg. Wish I knew about them not liking N for my last grow when I attempted to grow their Malawi. At least I now know what to do when I eventually try growing their Golden Tiger x Panama strain.