Temperature

They seem to be healthy, for now. Add 1/2 fans. My girls are growing happy outdoors with average 29 C° (peak 32 C°).

I have no air extractors, and my LED lamp make some heat. So i keep the tent partially open, never totally closed. I have some "air windows" on the side of the tent, but it's not enough of course. So i keep the top half of my tent door open. The hot air rise up, get out of the tent by the opened door, and with the fans, I'm totally fine, never over 30°C. Try to "stock" fresh air during the night. Maybe have you a fresher room in your house ? You could also desync your lights : ON during the night, OFF during the day. Anyway, If you can't manage to stay under the 30°C... I advice to never close your tent. Not sure about this one : You could freeze water bottle every day, and put them in your tent. This **may** help. Also, maybe can you move some electrical devices that heat, out of the tent ? (power split, power block...)

i would leave the fan on all the time, and not just when the light is on.. you will still want to remove the stale air and get some circulation around the plants.. and during flowering, you will have to do that too, so it won't smell up the area (if this is an issue)..

I do have fan indeed , it's on time works same hrs as the light 16/8. I try to open in several times a day to spray some water. In a day time a leave zip a bit open so the air can get out and than the temp is around 30° , also watering it every/every second day with not too much water trying to keep it monitored so it doesn't get wet but stays moist. Its soilless and in material pots to not get too wet

So you have extraction fan, if not get one ASAP. You need to exchange the air in the tent. Intake is not as important for a small area but you must pump old air out! They will survive high temps during veg but not forever. And then you'll be watering more often too which isn't good, try to get the temps stable