Generally Moss raises the humidity, so it´s not for species that should be kept dry.
Live moss needs a lot of light to grow in a terrarium and it should be put into quarantaine, if you colect it from the wild.
Dry mosses like sphagnum or other comercially sold terrarium mosses also raise the humidity, but, as they are already dead, dont need light or watering. They are more recommended to be mixed into your substrate mix, but of cource they can also be laid on top of it.
You can overdo it, if the humidity levels, you reach are too high for the animal you keep. Can be problematic with live moss, as less humidity might kill it, but dry mosses can just be let to dry a bit and then it should be fine.
NewSphagnum moss is usually the ideal way to go. In my opinion, too much is a bad thing though. What species are you planning on using it for?
Mexican red knee isn't necessary. If you do make it sparse. A little here, a little there. As for the Goliath, you can but much more. Just don't over do it. The sphagnum moss is there primarily for looks and humidity retention. In my opinion the Goliath would be the only one I would use moss for unless you mix it directly in the substrate.New
hi i was going to put moss in with my Mexican red knee, chaco golden knee, Haitian brown and Goliath