Heat problem

K so i have a closet grow of about 3 feet by 4 feet by 5 feet. I'm using a 400 watt lamp and the whole thing is cooled with a fan blowing out by the light and another fan blowing in by the soil. The temp is usually around 26-32 degrees celsius. but the soil seems to dry out really quick cuz of the intensity of the light and probably the dry heat in the closet. is there any way i can improve this or solve it?

Better ventilation combined with a more regular watering system should do it.