[mwarsell]

I've currently got five dwarf pencilfish (nannostomus marginatus). Can I add mortenthaleri or rubrocaudatus to these? Or does it have to be the exact same species?

 

[Flint]

I know with almost every other shoaling fish it has to be same-species or they shoal out of stress/necessity which isn't good for them. I am not sure if this is true of pencilfish or not but I'm sure someone will be along shortly to answer more specifically.