This all depends on age. Are you talking about fish that have already paired up? Then 2 pair should be ok. If you want juvis; you can get a bunch, let them pair up, claim their territory, and then deal with the problem of getting the others out. Sounds like you may be thinking of breeding them; if so, I'd suggest you post in the breeding section.
Personal note: I see you're in Elko and miss the keys. I went to College in Reno, then lived in the Keys for a few years a lifetime ago.