Im running a 600watt hps (Not air cooled) in a 1.2x1.2x2m grow tent. I have a 4" extractor to the room & 4" intake from outside, but im looking to upgrade to a 5/6" extractor next weekend as I haven't achieved negative pressure. The temps get around 24c in there at GROUND level. Is this ok for seedlings? As in freshly sprouted seedlings..around an inch and a quarter tall. Sorry if I sound ignorant! Im new to this and started off way too early..Lesson learned! Any help is appreciated. EDIT: The small leaves out of the 4 (Not sure which they are) are curling in slightly at the sides, is this a problem? I've looked on the web but can't find much.. maybe over watering?