Can you help me sort the 4 families of tangs and give me your favorite choices?
I got a 90g and a 15g filled sump.
All tangs are in the same family, Acanthuridae. Within the family, there are six genera (plural for genus):
Acanthurus - big catch-all group with powders, achilles, convict, and others
Ctenochaetus - bristletooth genus with tomini, kole, and close cousins
Naso - huge, but gentle giants
Paracanthurus - just the one, regal/pacific blue/hippo/pallette/Dory or whatever you want to call it
Prionurus - sawtails. Really large tangs that we don't see in the hobby except for sometimes P. laticlavius
Zebrasoma - Popular group with the 2 big sailfins, yellow, purple, black, gem, scopas
But I have a Tomini and a yellow tang that are besties, I'd like to add a third one but I don't know which would be as pacific....
For a 90 gallon, that will be tough. The 2 you chose may be the best 2 you could have picked for a duo. The smallest tangs, and best ones for a 90 would be the Ctenochaetus, like your Tomini. The smaller Zebrasoma (not the 2 sailfins) would be the next *best choice. The other groups get pretty darn big for a 90.
Personally I wouldn't rock the boat with more tangs. If you want another bigger, similar fish, a foxface would actually be a better option than another tang. With their dorsal spines, tangs tend to leave them alone, generally, in my experience.
Hope that helps.
