Oh wow ive been leaving them around 23-25 never more than 25 im using an se3000 300w at 70% 80cm above canopy. It gets pretty hot so i use the ac in my room to cool it down. Ill keep it at 26-27 for now. Do you keep it that high into veg? Or do u lower in veg?
Nice light. I'm looking at that or a viparspectra ks3000.
I generally keep around 28-32 in veg and around 50-70% humidity. Always get good posture in that range. In flower I'll try and sit around 27c if I can as we have a lot of flat mites (false spider mites) around here that love hot dry weather. I don't normally have issues with droop in flower though, it's always veg for me and I fixed it by upping the temps a bit in my case, and keeping the medium moist.
Here's the last four around day 23-26 and roughly 30c/65%.
Thats about as dry as the medium ever gets up top.
What's your light intensity as well? If I get issues with posture early on I find dialing the lights back a few hours always had them standing up the next morning for some reason.