I currently have 2 (1 albino, and 1 tiger) in a 110 high. I have only seen them liplock once and the larger one settled that pretty quick. Other than the two O's I have a few different types of dither fish to keep the O's attention off of each other all the time. I would toss in a couple of tinfoil barbs, there shiny and quick plus grow to monster proportions... Maybe I'm just lucky with my 2, but this thread was the first I ever heard of 2 oscars being a no no.