Don,
Thank you for the helpful information. I should have elaborated a little more. The fan would be a minimal size and it would be positioned above the lamp blowing hot air down. I would vent the tank on the top in some areas and test appropriately before adding the frog to the enclosure. I am not sure what kind of cover/top I am going to use. It seems I need two lamp housings a fan setup on one and a couple of flaps to regulate the temp. My Temps are pretty cold now and the room he is in is colder than most. That's why I use a 60w red bulb on a five gallon with a small heat pad. Temps are 87 during the day and about 75 at night. However, I will be moving soon. So, his new environment will need tweaking. Just wanted to focus on a cost effective solution that would minimize temperature loss. I think with a combo of heat lamp, aqua heater and heat pad I will be able to regulate his temps.

I never thought of using foam as an insulator but it certainly makes sense. Thank you for all your help. I will keep posting as I progress.

Thanks again.

B