i love when 'shrooms pop up unexpectedly. but try growing them intentionally? it's a nightmare...lol if that is tropical sheet moss i see in there, that is probably where the fern and 'shroom spores came from.

ah, you must mean dendroboard, where everything except broms, creeping fig, tillandsias and less than 1/4" of water is a health risk to frogs.....LOL