I am currently in the early planning of a palidarium of a 80-100 litre tank for vampire crabs, and with rasboras, shrimps and clamps in the water part. Gh: 9 Temp: 27 C PH 6,5 I want to have a lush environment both above and beneath the water, with moss covering the surface and downoi covering the bottom. Explanation for the picture: A: terrarium background made with bogwood, expanding foam and silicon covered with coconut substrate. Kind of like this http://bigalsonline.blog.com/files/2011/08/IMG_1342.jpg B: a rocky part of the background forming a waterfall. I plan to use real rocks attached the same way as the bogwood to get a more natural feeling. C: Will create a border here of rocks. On the inside I will have a layer of hydroballs covered by film with a layer of plant soil on top of that. D: Pump. I plan to have the pump here and have a hose going inside the background to the waterfall. E: Sand. Here there will be a layer of fine aquarium sand, on each side plant substrate with carpeted downoi. F: Paphiopedilum orchid. Around the plants will be a carpet of living moss. I will add specialized soil around the individual plants. G: pinnatum aureum, ivy, climbing over parts of the background H: Nepenthes lowii, Low`s pitcher plant I: Peace Lily, I may try to have some of the roots submerged in the water below. This is my first time doing a setup like this. So I try to be thorough and careful. A couple of questions. 1. Will a waterfall put together with several pieces of rock mended with expanding foam and silicon hold? Can this kind of construction take high humidity or submersion? 2. What should I do for air circulation? How much is necessary? Will appriciate any feedback.