First of all, thanks for the response. I'm going to chop your quote up in order to respond. Everything I write is just me trying to give you my thought process.
I was thinking that if there was a small water feature in front, then I would be able to easily siphon water directly out from there. No space sacrificed for PVC running the full height of the tank behind foam. Will this work? I've also seen people put short PVC pipes under a piece of moss in the front, so as to use less space. I'm looking at imitators at the moment which is another reason reason I thought I could sacrifice some floor space, as they like to climb.
That could work too The main thing is to think about getting water out of th drainage layer is needed
How thin can I get the spray foam? Ideally I'd like to go real thin, but I've heard it expands like crazy. Could I get it .5 - .75"? If I get going and it looks too small I'll certainly forgo covering any of the sides.
Spray foam can be very thin. If it gets to thick you can use an old streak knife to carve on it after it dries.
I'm concerned about humidity dropping if I'm away for more than a day. Assuming I will have the viv 98% airtight, what would happen if I didn't mist for 2 days? I can also guarantee I won't hand mist weekday mornings. Maybe I can put the mist king off until I decide to build another viv, and hand spray for now.
You will know after the tank is up and running for a week or 2 how long you can go between mistings. If you are going to be gone for a couple days you need to also consider how and what will the frogs be eating while you are away.
Eventually I'd like to do 3 12x12x18's, with 2 18x18x24's underneath on a custom shelf of some sort, all on a mistking. I tend to get carried away

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At that point a Mistking would make total sense. You could use one on the 12x12, it would just be an over kill and you would need to play with the timer settings to make sure you down flood the tank.
How do these ceramic heaters work? It looks like they go into a light fixture, would it work with the clamp lamp I have buried in my basement? Will an undertank heat mat work? If so I'd prefer that just because its less visible. This tank will sit on my desk for the immediate future, so it will be a real display piece and i don't want it covered in unnecessary gadgets.
Yeah they go in a light fixture or clamp lamp type thing. If it is going on your desk I would use an under tank heater, but put it on the back of the tank so it doesn't block your view
There's no such thing as too much information
