Morning mate

I think your going to have to get a better air exchange system on the go can you get a bigger intake fan? You will find as your plants get bigger the temps will rise more as leaves will slow down the air exchange. Also at this stage I don't think there is any need to be running 250w CFL while your babies are so small. You mentioned that you have some smaller powered cfl I would go with them as close as possible for now and work your your FAE (fresh air exchange)
best of luck brother
did I just read in another thread that one seed failed? I would hold back poping another one until you know your temps are going to be under control. Also you will probably get the same amount of bud doing 2 plants in that area with CFl because the light penetration will struggle to get to your lower bud sites, also with 2 plants you will get better FAE
just my"My 2 cents"
I have a friend that had the same problem with a fridge grow, he tried to cram too many plants in and ended up with hard buds on top and loads of popcorn below