Once Brichardi pair up they can be real terrors, however, they are amazing to watch... they raise their young in a big family unit.... the older siblings join in on the parenting etc and they live in one big family... interesting to watch that is for sure... If you wanted to keep more than one tangy species in the tank then it would pay to have a nice amount of space and good territory areas set out... I have had Dafs and Julidos live quite happily together till a pair of Dafs decided to want to spawn and look out Julidos, the poor little battle subs were cowering in the corner of the tank right up the top, it was a case of removing them for their own safety :lol: You could keep a single sex only tank and see how that worked, or alternatively you could just keep the one species...?? Or try and make it work with 2 species and just keep your eyes peeled at all times.