What is this plant?

[envirosci]

Cool. I'll be sure to get some polka dot plants then.

I just don't want the creeping figs to take over the entire tank.

[B Jet]

looks good. My advice is also against any secondary pots in the substrate... a healthy viv requires near-constant pruning, resulting in more compact and robust plants. in my experience, vertically-oriented plants such as the philodendron or ficus, if left unchecked, will form a dense canopy directly under the lid and choke out light reaching the bottom. I recently got a few books on bonsai, and they have been very helpful, though it doesn't neccessarily apply to all plants

[JimO]

Actually, the creeping fig is a great viv plant. Keeping it in a pot won't limit its growth at all. It sends out roots at each leaf junction. I've started it with a cutting high on the background of a viv with just a little sphagnum moss. It grows fast, but not so fast that it's unmanageable.