Lime Loving Miniatures?
 

Hi! I'm wondering if there are any lime loving lithophytes which would remain small enough to stay permanently mounted on a rock in a terrarium of about 1/2 gal capacity? I'd like to do something similar to one of those biospheres, with a couple Volcano Shrimp, a Nerites Snail, both of which greatly prefer hard or even brackish conditions. I don't plan on adding salt of course, but my tap water is about 200ppm hardness and I have really beautiful small pieces of aragonite to use as a mount. Also I have no need to "prove" anything here, so the container will have a removable lid to provide for gas exchange and general maintenance. TIA!

Most cattleyas do well in high-calcium conditions, and there are lots of miniatures to choose from. But they do tend to spread out. You can also try a Doritis pulcherrima (a phal)