Be aware of common names, because several different plants, none of them true mosses, are called Irish moss. Some species of Selaginella go by this name, and while not true mosses, these "club" mosses grow somewhat like small ferns and are appropriate for a terrarium, if not for a ground cover. The other "Irish moss" that I know of is Helxine soleiroilii, also known as "baby's tears," and is totally unrelated to mosses, but is still a decent terrarium plant, with small delicate leaves and a creeping habit. "Scotch moss," is also a Selaginella--specifically S. brownii, and not a true moss, also a club moss, but equally appropriate for a terrarium, if not a ground cover like the true tropical pillow or sheet mosses would be. Who knows what other common names commercial folk give to totally unrelated plants? They tend to assign them arbitrarily and without conscience. Some perennial blooming plants are know as mosses: witness "Monterey moss," which is a blooming succulent Mesembrianthmum, about as far from a moss as you can get.
Your "mosses" are appropriate for the habitat, but may not cover the ground like you expect. For this, you need one of the tropical pillow or sheet mosses (which are more difficult to grow, actually,) or the longer Java moss, which will cover anything that is wet, but with longer, more untidy strands than the pillows or sheet mosses. This is easily controlled, however. When Java gets out of hand, because it is very enthusiastic, you just rip it up easily and it doesn't argue about it or take a lot of substrate with it. I love Java for the fact that you can always get rid of it where you don't want it, at least for a long, but ultimately temporary period, and it will grow both under water, over substrate, plain rock up water-falls, or anywhere that is damp, without being overly fussy about light. It's a great water filter and purifier for ponds and aquarium features if you incorporate these in your tanks.
Here's a picture of Selaginella krausinna brownii, also known as "Irish Moss."

-----
Patty
Pahsimeroi, Idaho
4 D. auratus blue
5 D. galactonotus pumpkin orange splash back
7 D. imitator
6 D. leucomelas
4 D. pumilio Bastimentos
4 D. fantasticus
6 P. terribilis mint and organe
4 D. reticulatus
4 D. castaneoticus
2 D. azureus
4 P vittatus
2 P. lugubris