See there you are dealing with a spawning pair at least that is what it appears to be. I have read of accounts of ca cichlids forming huge multi species schools. When they are not spawning. Now of course your large piscavore cichlids do not do this they are probable there but to feed on the more smaller cichlids. I like to use sunfish and crappies as exsaples u go fishing for them and you catch greens blue gills white and black crappie all in the same hole by the hundreds. Now they say cichlidia is not present in north amarica because of the Sunnis and bass that are here as they fill the same ecological notches.