Temperate zone mosses don't seem to last long in tropical tanks in my experience. But it probably wouldn't harm anything to try it out. I don't personally worry about introducing insects and other small critters into a tank. Once the biological process of cycling with frogs present, their populations will be controlled rather well. I can even live with a few slugs and a little bit of leaf damage. The only stubborn problem I've ever had was scale insects on a bromeliad. But little soil mites, springtails, gnats, tiny millipedes, you might find on moss are more beneficial than destructive.

Here's one of the detritus-eating millpedes on some moss in one of the tanks.

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Patty
Pahsimeroi, Idaho

Dendrobates: auratus blue, auratus Ancon Hill, tinctorius azureus, leucomelas. Phyllobates: vittatus, terribilis, lugubris. Epipedobates: anthonyi tricolor pasaje. Ranitomeya fantastica, imitator, reticulata. Adelphobates castaneoticus, galactonotus. Oophagia pumilio Bastimentos. (updated systematic nomenclature)