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.

Quote Originally Posted by DigitalPunk View Post
Hey, late to this thread. Been lurking but have failed to respond.

- Leca - Be sure to hide a tube (PVC works great) in the spray foam background so you can syphon water out of the drainage layer. It will make your life a lot easier as time goes on. You can then stick a small tube down the PVC pipe with a sponge on the end of it and syphon the water out. Leca is usually recommended to be 1 - 2in, but you need to be careful with the small tank height that you don't chew up 4 or 5 inches of space with the substrate. You will also need to keep in mind that if you are going to do a small pond the Leca layer will need to be a bit higher than the top of the waterline to keep the water from swamping the soil. I would recommend against a water feature in the tank to conserver space, but that is just my 2 cents.
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.

Quote Originally Posted by DigitalPunk View Post
- Spray Foam - Keep in mind it will expand so be careful how thick you lay it on. Anything you do will shrink the usable floor space for your little frogs. Keep in mind if you add 1 to 2 inches to the back wall you have reduced the floor to a 10x12 square. If you then do a 1 to 2 inch water feature then you will be left with a 8x12 square. If you add foam to the sides you could end up with a 8x8 square which is to small for even thumbnail frogs. You could consider doing a planted terrarium and using some wood to create hight and tie bromeliads to them.
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.

Quote Originally Posted by DigitalPunk View Post
- The Mistking will be a huge overkill to the tank. I love my mistaking, but in a true dart frog tank with near 0% ventilation the humidity will stay high and you will really only be misting to keep the plants growing. I use a hand mister on my Dart tank and my Mantella tank. The humidity in both stays very high all the time so misting them once in the morning and once right before lights out is perfect.
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.

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 .

Quote Originally Posted by DigitalPunk View Post
- Heating - There are a lot of options out there. My Favorite is now using Aquatic heaters, but in your setup a Ceramic Heat emitter will work great. It doesn't dry out the air, provides 24/7 heat without generating any light, and are cost efficient to use. You can use them in conjunction with Zoo Med Hydrotherm.
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.

Quote Originally Posted by DigitalPunk View Post
Sorry for the information overload. I'll answer any questions you have that I can and can't wait to see how the build turns out!

Paul
There's no such thing as too much information