Ok I have tried both having the fan suck and blow and I'd have to say it works better sucking.. it may shorten the life of the fan but it will clear alot more heat alot quicker having it suck instead of blowing.. Also because the light is cooled hence "cool-tube"
you can have the plants touching the cool-tube no problem
providing the air you use comes from a different room with cooler temps or an AC unit etc then YES you can have the plants touching the tube and it will be mildly warm
I also have a 250w ballast and a 400w ballast and I will prob start with the 250..... get that grow out the way and make notes then do the same for the 400 and then finally the 600 hardcore one.. But I am going to document the whole thing in this thread so feel free to leave comments, ask questions and well you get the idea
keep watchin buddy more to come
- STELTHY