I like aquarium size gravel as a bottom layer then apply whatever substrate you prefer. I use a layer of bark then a combo of moss and soil. It sems to work quite well and the plants love it. Oh, and as for the geckos eating substrate debate, my sikorae eat it sometimes and don't seem to suffer any ill effects. The air is fairly dry here...I don't have a humidity gauge in the house but I would expect relative humidity to be around 50-60% outside. The humidity is easily controlled in the tank by misting though.
post pics when they arrive, I'm sure everyone would love to see them. I was interested in the lineatus that he had but they're gone already. Poeple really love these guys!
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ryan
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Uroplatus sikorae