I'll tell you what will happen, if both pairs are of breeding size, one male is going to kill the other and then you'll have a trio. Set up 2 tanks, one for each pair of Cacatuoides and find some place to put the hatchets. They might end up becoming a problem once a pair spawns. That would be my recommendation. John ------------------------------------------------------------------------- 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. Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!