The humidity in my Do-It-Yourself wooden tank wasn't high enough, so I added a Do-It-Yourself humidifier like this:
Helping herp hobbyists! - Sections - Do-It-Yourself (Do-It-Yourself) - Homemade Humidifier
This wasn't good enough for my tank, so I used my thinker and came up with a more efficient design, which is working well so far.
I took all of frank's stuff out of the tank, leaving only the false floor and some wires. The black paint spots are where the gaps in his rock background are - the black does a pretty good job (i think) of making it appear as though those gaps go really deep.
I used a 2" high (the amount of space under my false floor) piece of tupperware from target and a 60 gallon whisper air pump ($20 or so at Big Al's). The tupperware needs a largish (2" in diameter or so) hole in the top to vent the humid air, and I carved out a little space under the lid along the rim through which the airline goes. My air pump has two outputs, so I put one to each side of that divider in the tupperware.
I also had to make a hole in the sheet metal with a drill and a nibbler.
Image:Nibbler1.jpg - Wikipedia, the free encyclopedia The hole is intentionally larger than the one in the tupperware, so that the humidity will (mostly) vent upward rather than around the underfloor area.
I also installed a SHT15 (available on sparkfun.com) humidity and temperature sensor. This goes to my Arduino microcontroller, which I programmed to switch on and off both the air pump and the radiant heat panel based on ambient humidity and temperature, respectively.
The black duct tape is for the cavern affect from before, as mentioned. It is actually held in place with staples + zipties. Stapling a ziptie to a board with a staple gun, and then putting it around cables, etc, is a good way to secure things in a wooden tank - you can see one on the right side of the picture.
I also drilled holes in the actual bottom of the tank to run the cables and airline tubing down to the pump and microcontroller underneath the tank. The airstones and such get plugged in at this point, too. They have enough of a gap cut out with a knife where they are plugged in that they are not constricted (important for airflow).
The heat panel on the ceiling and the air pump are controlled by the microcontroller, but I have a Under Tank Heater as well, and it is on a separate cheapo $30 thermostat (set to the higher basking temperature).
EDIT: This configuration worked OK, but in the end I took out that piece of styrofoam, under which the thermostat probe is. Then, I put the Under Tank Heater underneath the water reservoir, curving it to be on top of the piece of wood so it has a configuration like this: _/- with gentle curves. This way, part of it is underneath the water to heat it up, and part is underneath the snake to heat him up. The thermostat probe is right on top of it in the new way.
This is my piece to cover the whole yet allow airflow, to make sure frank doesn't go into the reservoir. It simply is a piece of grout-primerd-styrofoam, with velcro attached at the back and on the underside in the front. It has large holes that aren't visible to the camera.
I needed to eventually staplegun the velcro to make sure it sticks, which worked great. However, I'm going to replace this with a circular ring of styrofoam (to stop reptibark from falling in the hole) and staplegun some screen material to the underside of the ring. I think this will allow for better airflow and humidifying.
This is the end product. Except for the hole cover, the tank isn't really modified in any way.
With the addition of the heating element under the water (noted in the edit above) and the reservoir with more surface area and a much bigger vent hole than the original gatorade humidifier, this setup works great as a cheap way to keep humidity up. My humidity rose from 30% to up to 40% very soon after putting this in, and it is still rising to the desired level.
Hope this is helpful, it should also be a decent guide on how my tank itself is put together.
Jim