I worry about putting them too close, heard that also could dry them out?
Yep. I have lost sides of plants where the fan moved and blew directly on them. It desiccates them. It is simply not true that closer is better (even with a cool tube). Plants breath through tiny holes in their leaves (stomata). They lose water like this in the same way that human breath is damp. If they lose more water than they can suck up, they will dry out and die. They respond to this by closing their stomata, holding their breath until it is cooler. Without inhaling CO2, they cannot photosynthesise. The light falling on them does nothing and so the attempt to increase growth actually inhibits it.



