Its a little tiny 1.5"- 2" plastic pot that came with some kind of succulent. Theyre usually found at walmart in the lawn and garden section. I just tossed the succulent into one of my terrariums and decided to use the pot for this particular plant. I put some live moss in it and just watered it a bunch until I felt like it settled in nicely, (moss seems to last me longer and grow better when packed tightly in a pot for me, possibly because of fewer air pockets to make things dry out perhaps), then I began a regular 2 to 3 day watering/flooding schedule for it. The little clear top that you see is just one of those microwaveable Rubbermaid dishes you can get at walmart or some place where tupperware things are sold. I found one that was slightly larger than the pot and bought it. I threw away the lid that it came with and turned it upside down over the pot. I just leave the plant covered like this day and night, and it is completely air tight. No holes for air to get in or out. It allows for very high humidity. Just gotta remember to take it off once in awhile and blow in there for fresh air (daily for a few minutes). I prefer to use a fan instead of me giving air to the plant. When i am not messing with the plant, it stays in a tray with a small puddle of distilled water in it so it never dries out. I do not put it in direct light. As opposed to using my strong leds for this one, i put it about 8" away from a couple of 6500k t8's and not directly under them, just off to the side. Been growing them this way for months with no issues whatsoever, and has given me several plantlets from pullings too. Its very similar in growing Utrics this way for me too, except i dont see much need for covering those unless they're introduced to a different environment, and that is only until ive acclimated them, then the lids come off.
I forgot to add, my method is what has worked for me in my conditions where im at. It may be something as simple as changing media for you or watering, etc. What may work for me, might not for someone else. Just some ideas that worked for me