Could this be heat stress?

[Lolabird]

Hi all,

Currently have 3 plants just switched to flowering. Over the last week I've watched this Sativa start to droop its leaves, it also has small bumps on its leaves and always has done right through veg. However the other plants aren't suffering the same issues.

Coco coir with 40% perlite
400W HPS sunblaster (I have the option to turn this to 250w)
PH 5.8
EC 1.7
PPM 700

The nutes are a tad on the low side so I've given feed tonight to see if there are any changes tomorrow. I've also changed to 250w.

Had some hot weather here for about 8 days and the tent has been cooking at 29C at 400W HPS and all fans on max. I know this needs to drop to around 25C ideally?

Any ideas what the bumps are at all?

https://imgur.com/a/9GrcDvm

https://imgur.com/a/n9kIY4P

This is just a wider angle shot showing the other healthy plants in the same environment

https://imgur.com/a/0jFbaOM

[crucialbunny]

It's really hard to tell what's going on with that lighting making everything look yellow. Try posting a picture under white light so we can see the true colors. From the droopy overall state of the plant I would lean toward your judgement that the environment could very well be too hot. I don't indoor grow so I am far from being knowledgeable but it is possible that instead of blowing them full blast with hot air with the fan you might consider putting a few bottles of frozen water between the fan and your girls to lower the temp a bit. Without hands on tent grow experience I'm just throwing the idea out there. Best of luck to you.

[UnderGrower4]

29C doesn't sound that bad, i think ideally you want it under 27C but i believe plants should generally be fine under 30C. what strain? What RH inside the tent ? +1 for natural lighting pictures.

My amnesia haze has shown no sign of heat stress during last week's heatwave and the tent got up to 30,6C at plant level.

[Lolabird]

thanks for the suggestions everyone. In future I'll try to get better photos. It turns out this was heat stress as lowering the temps has made the back sativa perk up alot, she must be more sensitive than the others.