do you have a humidifier in there? if not then get a few wet towels and put in there. the humidity will help with the heat. at least until you put them into flower,
well we have 4. we had a semi-problem we set off with the idea of 5. but this maybe just me but the 2 big plants barly fit under the HPS. so i think 3 would be the max i would do next time