My terrarium is an old 2.5 gallon bow-front aquarium. It's so far doing well as far as space with the Drosera Admirabilis "Floating" and Red Dragon VFTs. However, the limited lighting I'm able to install (if I want to continue using the stock hood) forces me to supplement that lighting with sunlight from my window. You can imagine that this causes it to get quite hot inside. Today the interior reached about 90 degrees, so I'm trying to think of some way to help with airflow to reduce the temperature. I think the best option is to get a small fan and rig up a conduit system that I can run through an opening in the top. I would like if I could just run a conduit system directly from a slightly open window, but I'd have to think of a way to seal up the rest of the window opening. Sorry to commandeer the thread :P but I thought I'd let you know what had worked for me as far as plant selection for my similar-sized terrarium.