Grow tent ventilation question

whats growing on? I am in the process of building a grow tent, ive built the skeleton out of some sturdy 1 1/2" pvc, there will be alot of stuff hanging from it, the dimensions are 2' x 3' x 5' , fits perfectly in my sliding door style closet, im gonna skin it with some black and white poly. the tent will be split horizontally in 2 equal halves, i am going to have 2 2' 108w t5ho fixtures on each layer. (im doing LST only) im not sure what type of fan I need in order to adequately draw out the heat from the lamps. I do know that i want to have a carbon filter at the end of the outtake pipe and i want to do all of this myself, so if anyone knows where I can get an adequate fan for cheap I would love to know, and also if anyone has any ideas on how to set up the ventilation on the inside that would be great, i was thinking something along the lines of a dryer type of flexible hose running down the corner the whole length of the tent with the end bieng by the bottom lights and a hole cut out for the lights on the top layer.

btw these lamps dont get to hot, but they are uncomforatble to touch, although they wont burn you.