Why is my soil so dry/please help with problems??

My soil keeps getting dry prematurely, its fox farms ocean forest. I have some seeds that sprouted long roots but havnt broke the surface yet, and they r under 400w hps and a small blue led grow light. Because they r young, the lights are about 2 and a half feet from the soil surface, in a grow tent. The tent has bad ventilation, I have two 6in fans and 2 ducts, one blowin air out, one blowin cold air in. The temps were gettin too high with the grow tent closed, so I have been leavin it open, and the soil is so dry that I have to water it at least twice a day, and I havnt even put them on 18/6 yet. When I water I try to give the dirt an even soak, about 1/4 gallon per gallon container, cuz they r lowryders. Please help me people. Also,are those little computer fans what i need for the right ventilation?

whats ya temps and humidity at?? maybe u should think about switching to a soil that holds moisture like a coco medium.

temp is like 90 and 25% humidity even if its open.