empty 10 gallon

How about Rummy Nose tetra? They school really well and are a pleasure to watch.
 
Neons need a bit more room than a 10g can provide. Move those 10 to a 30g tank and you'll see much different behavior, IME. ;)

For a 10g, Ember tetras would be great. Also, if you can find Microrasboras, they'd be good as well.

Harlies are ok, though they are pretty active. A 20g would be a better minimum for them.
 
i had 8 zebra danios in my ten gallon. they seemed fine....till i got my dempsey and the 29 gallon. now they hide from him:mad2:
 
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