Hulkberry went into flowering and is stretching now.
Purple Queen should follow soon.
I turned up the light to 100%. Since PQ is a lot lower it should be fine even though it's not flowering yet.
Friday, Day 32:
Hulkberry stretching nicely, now at 52cm.
I noticed some brown spots on the tops leaves. Wondering if this is a nutrient problem. Recently these leaves also started curling upward, so it also could be heat stress or light burn.
Increased the distance to the light to 45cm. The timelapse also made me realise the leaves start drooping quite early each day, about 2-3 hours before lights out. So I extended the sunrise/sunset period to an hour.
If this does not help I will reduce the light intensity and/or duration.
Update:
Just gave Hulkberry some extra Bio-Grow to counter the Nitrogen deficiency. Calmag is on the way, which will hopefully help with the brown spots.
Thanks to everyone in the replies on my grow question.
Looks like I underestimated how hungry she is. But it makes sense, since it is a rather fast Auto (RQS says 8-9 weeks from seed to harvest). The Bio-Bizz nutrient schedule was designed for up to 10 weeks of flowering phase.
Purple queen still taking things slow. Probably needs another week before flowering.
As suggested in the comments, I have propped it up to counter the height difference.
Day 34, Sunday:
Hulkberry got a bit of its color back after getting double doses of Bio-Grow to get some Nitrogen in there.
The lower leaves are as good as gone.
Also started giving some Calmag.
Purple Queen looks like it's about to go into flowering phase.