Archie, I'm certainly no expert, but I do know some of the terms these guys like to use. There are singles, pairs, trios, and harems. Usually one male and one or more females. I have read that Trifasciata and Cacatuoides do well in harems, but that was just one book. I also know that what works for one breeder may not work for another, but maybe someone here can give you general guidelines. I think your suggestion of two varieties in a 75g sounds fine. Maybe two trios. Three pairs might also work. Just my 2 cents. -Jody ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. apisto-digest@listbox.com also available. Web archives at http://lists.thekrib.com/apisto