need a pure black fish

Black goldfish won't stay black for a long time even if there is one that would fit well there. How about black mollies, guppies and swordtails? Black bettas are very rare though. Hmmm...Black neon tetras?
 
how black are we talking? lol

Black skirt tetras are pretty dark, there are some small shrimp that are black too
that msjinz is selling

G'luck
 
I don think I have ever seen an agressive molly

they are quite peacful fish from what I have seen
 
Black Molly would've been my suggestion as well, it's about as pitch black a fish as I've seen.
 
Whoever told you balloon mollies are agressive needs to do some research...

they arent any more agressive than a platy or guppy.. they just have a bit bigger mouth

I have balloonies in my community tank and they dont touch anyone else
 
Molly or Balloon Molly will be fine!
 
Black Moscow Guppies
 
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