I think you're rigt about putting the priority on surface area vs. depth. I'm leaning towards 5X4X2.5 or maybe even 6X4X2. I'm not looking forward to the monthly charges for maintaining this thing.
:how deep I should make it vs. surface area. What do you guys think is most important? I've toyed with 5' wide X 4' front to back X 2' depth. Or 5' wide X 3' front to back X 2.5' depth. Any suggestions are greatly appreciated.
::Kevin :With the size of your turtle, I'd go with the 5'x4', this would give you more room for hide area. I think the 3' front to back would look a little cramped.