Juan,
Thanks for the tip. I checked out the web page you mentioned. It was a nice
discussion on the various points involved. I had a tank with one fish (a
cichlid) in it and I decided that I was tired of having a 40-gallon tank
with only the one fish, so I went out and bought three additional cichlids.
The largest of the three new fish became the dominant fish. The original
fish is now hiding in a plastic "cave" that I bought. The smallest of the
three new fish has torn fins from the pestering of the dominant fish.
It is frustrating. Cichlids are the most interesting fish to keep, but it
seems they are the most difficult to keep together. Except for kribensis
and rams, I have always had problems with aggression.
I think that the statement in your discussion about no hard-and-fast rules
is correct. In fact, it seems to be hit-or-miss. Sometimes, the fish will
get along, and sometimes they won't. You just never know.
David Salahi