Help
This plant is on it's fourth week in veg under a 600w HPS in a homemade drip feed system. EC is about 1.0 which amounts to about 2/3 of full strength veg feed, but still keeps rising. Temps are allright between 24-27c. Lights are 18h on, 6h off. Earlier the pH used to rise quite fast, but is now under control at 5.5-6.0. The lamps is quite far away from the tops, maybe 80cm or so. RH is probably on quite a low level, but I don't know the exact amount.
So, the problem is slow growth, smallish dull green leaves with often darker green veins. Lately I have been noticing burning/drying leaf tips and dying lower leaves. First I thought that the burning was due to overfeeding as the EC had risen to about 1.35 at one point. Now I have speculated about possible N def, but at the same time wondered if it's possible as the EC keeps rising all the time.
Here's some photos of leaves, plus one crappy HPS illuminated photo of the whole plant. Unfortunately I'm currently unable to get any better ones. Anyway, any help would be greatly appreciated
