The hot air from the reflector wont be going into my veg cabinet. It'll go a lil sumthin like this:
fresh air from outside ---> flowering cab -----> up to veg cab ----> back down and through the reflector ----> away. So basically instead of the RVK sucking air from the main cab through the reflector, it'll suck air from the veg cab, which will get its source of air from the flowering cab, and this air will go through the reflector.
I'll try and model up so you can see what ive got in mind. The shopping basket for this little project is £210 so far for lights, fans, mylar, AIRPOTS!. I want to upgrade my RVK as the ducting it'll be pulling through will be longer. Also gona use FRESH inline fans (5") to help move the air through the ducting. If i go with T5's which i probably will now, i can leave a little gap between the 2 cabinets, like 6" or so, and snake the ducting in this space to prevent light pollution between the 2 cabs. This will also be enough space to fit an inline fan in, so no space is taken up in the actual cab.