Ideas for a good schooling fish?

I'd also concur with both Harlequins and Rummynose tetras. I've had Harlequins before, quite beautiful fish although once they become used to their surroundings they tend not to school so tightly.

I currently have a school of 8 rummynoses in my 30g and they are great schoolers, when their color is up they are fantastic to watch! :D
 
Harlequin Rasboras seem quite popular. Try some scissortail Rasboras. They reach about four inches and are very peaceful. They have the "ghost fish" transparency and have the same kind of movement as neon tetras (darting, stop-and-go thing).
 
Thanks for the advice everyone! I'll probably add a shoal of one type this weekend and if things go well, I may add another, perhaps smaller, shoal in a few weeks. I'm leaning towards rummynose and Harlequin (not sure why, but many LFSs around here call them "T-bone rasboras" hehe). I also haven't ruled out zebra danios -- I've always liked them, but they tend to stress out other fish with all the constant darting to and fro.
 
I've gotta say, I have 10 zebra danios in my 29 gallon tank (the only fish using the upper half of the tank, even) and they don't school at all! I was a little disappointed in that, but now I like the "busy-ness" they provide the tank, since my other 3 fish generally use the bottom 1/4 of the tank.
 
ha! the black on them does look a little like a t-bone! I always called it a triangle.
 
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