Don't buy this fish for a community tank! They're bullies, and despite their size, they can be very tough on fish much larger than they are. Check these links. Also called the Dawn tetra. I just took 6 back to Petsmart 'cause they were terrorizing a 75 gallon community tank. The Rummynose, Blue tetras, Gold tetras and several others had disappeared into the foliage to avoid them. They were relentless, and not as a group, but as individuals running at anything that moved.
http://www.tropicalfishkeeping.com/characins/panda-tetras-68559/
http://www.tropicalfishkeeping.com/profiles/dawn-tetra/
I had the exact same experience about five years ago when I bought 8 serpae tetras on a whim, to add some colour and variety to a 75g community tank. Huge mistake!
All though I've seen the ones at wolfiewill's and they seemed docile, the blue (cochu) tetra's, were a mistake for me. I originally bought eight and they were chasing each other and the other fish. I then bought another eight thinking that they needed a bigger school but no changes so they went back.
I also have serpae tetras. At first they were very nippy but it was only with each other. As my columbian tetra's grew bigger than them, they seemed to realize that they didn't own the tank and now they usually stay in the plants for the most part. They all seem to have established their own territory and when another serpae comes close, they get chased away. My bleeding heart tetra's do the same thing.
Agree with Lucius, I have the same experience regarding the Serpae and Columbian Tetras.
But thanks for the heads-up on these tetras Wolfie!
Buenos aries tetras are extremely aggressive, another to watch out for
I had serpaes in a group of 9 when I first started keeping fish, they were fine by themselves, but when I added glowlight tetras, I learnt about disease pretty fast. All the glowlights broke out with fin and tail rot. I recently brought home a group of eight Columbian tetras. I had them with very young angelfish and BN plecos. They were fine as a group and their group even grew to eleven in 6 months. Only tetra Iv'e owned that spawned to have fry actually live to adulthood. I think they are beautiful fish. As for the serpaes, I now choose red phantoms. They are nothing like serpaes, personality-wise, and become a brilliant scarlet colour.
Thanks wolfiewill for the warning.