The dimensions are 18W 30L 24H, which I guess comes to about 57g. I built the tank myself using an old 20g frame (removed the frame and cut it width wise to stretch it out to 18") and 1/4" glass. In the end the frogs get as much vertical space as floor space, but I find they take good advantage of both.
Lighting: I recently switched to AHS 55W 6500K which is excellent and has brought out the red in some plants. All of my epiphytes are actually pinched from those tacky “air gardens” they sell at grocery stores.
Maintaining the water feature: I just do regular water changes with a siphon every few months. The setup is actually a “modified” false bottom, with false bottom islands on the left and towards the back. The islands are built with PVC and coroplast (
http://www.coroplast.com/product.htm ) which is cheep and an excellent structural building material for vivariums.