Two, if you get a pair, should be no problem, sveni pairs I've had might fuss and chase a bit at times, but that's been about it. If two aren't a pair it can depend on gender, individual temperament and what else is in the tank, similar with three. I have three in a tank after moving a pair to another tank. For a while they had a tendency to fuss with each other after two of them formed a pair for a while (based primarily on behavior with each other, they appear to be two males, one female). Nothing serious and they've since settled down to be quite peaceful, which was after adding an adult male Heros notatus last year. He's the tank boss and since then the pair seem less interested in spawning.
I've seen people do single adults also, they may or may not boss the tank, but it normally seems to work, assuming compatible tank mates. I've had geos for close to 20 years, now, and while a group makes a nice display and I enjoy their social behavior, the 'geos need to be in groups' thing can be overstated, especially for adults.
Differences in gender mix, individual temperament, tank mates, tank size-- some people overlook these things when they dogmatically make predictions about what will or won't work, especially if their experience is limited to a single group. Some fish don't follow the rules.
I've seen people do single adults also, they may or may not boss the tank, but it normally seems to work, assuming compatible tank mates. I've had geos for close to 20 years, now, and while a group makes a nice display and I enjoy their social behavior, the 'geos need to be in groups' thing can be overstated, especially for adults.
Differences in gender mix, individual temperament, tank mates, tank size-- some people overlook these things when they dogmatically make predictions about what will or won't work, especially if their experience is limited to a single group. Some fish don't follow the rules.
