As a fan of orchids and saltwater reef aquariums myself with a viv, I have found that some orchids do incredibly well in dart frog vivs and some don't too well.
Like you mentioned, orchids require more airflow than other plants, some species more than others, especially in a high humidity (80, 90 % range) for instance I had a pair of moth orchids that did wonderful without any air circulation for over a year before starting to rot a little. What you can do is install small computer fans over the top or drilled into the sides to move air without necessarily allowing too much moisture to leave the system. So, with fans to circulate air [some] orchids can do fine in a high humidity viv setting.
I do think that most orchids get too large for a 29 gallon, eventually. I would encourage you to continue looking for a smaller species but keep in mind that even relatively small orchids can still take up space and reduce the biodiversity of plantlife.
For lighting I've gone with power compacts (pcs), I would also recommend VHO lighting as well but I don't think that standard flourescents cut it. I've found the 67OOK spectrum workout and look the best although I also have 2 7100K bulbs and 2 10000K bulbs in addition to my 2 6700K bulbs, 65 watts each over a 55 gallon viv. With that much light, overheating can be an issue.
With heating as an issue, in regards to your question about the bottom of the viv, I made a false bottom with a layer of egg crate, hidden of course, underneath mesh, varying size grades of gravel, coconut fiber, than my dirt on top( Gravel in front and to the side of). There are a couple inches of water underneath the egg crate which is held up by pvc pipe. The added water volume helps regulate temperature by absorbing heat, and with an automated heater on a timer you can turn the heater on overnight and keep the water beneath the dirt warm. The pump could go beneath the egg crate and screen and protrude up through the bottom through rock work to create a waterfall. This is hard to describe without drawings.
I hope my input helps.
>>Hi All,
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>>I am kicking around the idea of building a vivarium/terrarium. I am fan of reptiles and have kept numerous species. I am looking to get my gf a little more interested in the reptiles field. She is a fan of orchids and saltwater reef aquariums (thus i am sure she will enjoy a tropical vivarium). What I am after is to make a very nice tropical vivarium and then add in a pair or group of PDF (depending on the type I decide to go with). My main questions are can orchids be kept in this type of setting? I have read that they like a decent amount of airflow but the frgo setups I was looking at do not provide this. I am looking at going with a smaller setup either a 15T or 29 gallon depending...15T would work better in the space we have but I have an empty 29. Do orchids stay small enough for this small of a tank? I was looking at the dendrobium orchids but could not find how big they get.
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>>Can other people give me recommendations on what specific plants to use to make this a very nice display tank? I am leaning towards going with a group of the yellow and black dart frogs (leuks).
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>>I am also planning a waterfall/stream? Is this best to do with a false bottom? Is the deep gravel bed with the pump in a container a better option (like Saurian describes), more attractive option?
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>>Would you recommend the 15T or 29 gallon for a better started tank?
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>>Any other advice/opinions are appreciated. Sorry for being so long, I just have found alot of information about necessities but not alot on what to make it look really nice.
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>>Thanks,
>>Scott
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