Right now i just have one fan, it's enough to keep the temp at 23º/24º and to give the plants a few wind. But i can easily add more if i need.
Temps maximum are about 22º/24º and minimum 11º, with the greenhouse i can increase a little the heat.
I've tough on t5s too, but i couldn't find any shop here selling those. I've tried to order a few of them but with the shipping costs and all those stuff they stayed really expensive! If you see the design of this growbox, it was planned for fuos lamps (i was thinking on 4, 5).
Maybe in a month or so i make another growbox and order T5s. Btw, the 22 watts CFL are a little expensive because they're cool white. You think it would be okay to buy a Daylight and mix them? If so, i would easily forget the HPS stuff.
I've cheap CFL daylight but just 11 watts i would have to use 6 or so and it would be hard to put all them horizontal (i've read somewhere that use them vertically waste too many light).
If it pays off, i cold use one of 22 watts cool white at the top of each plant and use a few more CFL daylight.