Are you talking about Ludisia discolor? If so, you just need to cut it off and stick in in some moist substrate... thats it. I guess if you wanted you could apply some rooting hormone to help it root faster. Offshoots of most orchids are called Keikis, but not sure if these are called that?
Ludisias display some really unusual rhizhomaceous growth in terraria, and mine constantly put off roots above the soil level. If you can find a place to cut where you are sure there is some root and leaves on either side, you can be pretty certain that your offset will do well in a terrarium.
I have even had growth from a small fragment of the rhizhome that was broken off by accident--it's still a small plant 1 year later, but it actually has leaves and everything. These plants are tough as nails in a terrarium.
Thanks for the definition of Keikis, as I just thought it was all plantlets on orchids. But I have heard them called divisions as well, so that clears things up more. Also, I think you could probably just chop up a Ludisia rhizome and get plants from it... but it would be easier to just cut off the new growth. I have had part break off and turn into new plants, so like Homer said Ludisia are pretty darn tough.
Thanks homer, both for the info and the comments on the frog.
I think it is a female, but not sure on the other one, the other is very shy and I rarely see it.
I have 2 more that also might be a pair, but the smaller of that set has been in quarantine for months with ups and downs along the way. Still kicking, but not sure one day its fat the next its not. So every time I think I'm ready to put it back in the larger tank I can't. Been thinking about putting them all together, but haven't yet.