If you ask 2 different people I'm sure you'll get...well 2 different answers! I have great luck with java which grows like mad for me. Riccardia (which is not what most people use and maybe you are thinking of Riccia), grows fine for me too, just slower. Now Riccia which a lot of people have good luck with doesn't grow well for me. I can keep it alive (most of the time), but it never spreads.
You'll just have to experiment with different kinds and different spots to put it and see what/where works best for you.
In the beginning LOL sounds like a Star wars movie, I was all worried about moss, now after the tanks grew in frogs and water did their thing not worried any more. I have lost quite a bit of moss, sheet mos and pillow moss. Tanks can get well get pretty wet (esp. when you pay more attn to feeding frogs,tads, juvie frogs than draining the tanks )-not a bad mother just a bad drainer. I have really had good luck with the saliginalla, I have used the plain ole jane ole "Zilla Terrarium moss" to fill in until the rest of the moss takes over. Meiks (New England Herptoculture moss has worked for me as well).
Just my 2 cents worth.
-Beth
worse comes to worse if you have a pet smart or any big box chain, T-Rex sells a "frog" moss. It's dry and in a dormancy. I bought a sheet out of curiousity. Get it in a humid tank and it will propagate.
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D. Auratus C.R. Green&Black 0.0.6
D. Auratus Nicaarguan Green&Black 0.0.2
D. Auratus Blue&Black 0.0.2
D. Auratus Green&Bronze 0.0.3
D. Auratus Ancon Hill 0.0.1
D. Auratus Reticulated Green&Black 0.0.2
I've found it really depends on the amount of light the 'moss' gets. Most don't do too well in low light. Most darts like low light. Many vivs I have seen are way over-illuminated, which may explain why many people actually hear calling and see activity after the lights go out. The darts are neither baskers nor nocturnal, so it makes me wonder...
I've found java to be the best lower light moss to use.