Mine were also a bit expensive I think - £4 each a couple of years ago - I bought 4 of them and they all died within a few weeks...
Shame, cos they were ever so tiny and cute to watch. I think some may have been eaten by the other fish (I assume as soon as they died) as I only ever found the body of 1 of them.
Yeah, they are very fragile little fish. I didn't know that at the time I bought them as I'd not come across them before. I'd gone into my LFS for some more sterbai but they had none. I saw the panda's and decided I'd have those instead. Stupid thing to do, really, as it was a lot of money considering how tiny they were. The fact that they are so delicate means you have to be absolutely spot on with their tank requirements and even then there's no guarantees they will survive.
There are, obviously, some who manage to keep them successfully, so if you really like them don't let us put you off. Just sharing our experience so that you're aware of the risk involved. All I can suggest is...read up as much as you can on them beforehand then you'll be better prepared than I was.
Regards, Athena