Ive tried to mix diff clowns with very little success. The first mix was 4 black perks and 2 false perks, the largest false perk took over and killed one of the black percs that may have become a female so she eliminated the competition. And this tank had no anemones to fight over and its 6L 30W 24T. I figured plenty of space they wouldn't fight....not!.
Second test is currently ongoing i mixed an established male and female black perks with a couple young naked clowns and to my dismay the smallest naked clown is being picked on by all the rest. I expected the black perks to attack the naked clowns right away but they didn't. They accepted them, and then 4 months later, they decided they didn't like the small naked clown. I will be moving him to a 50g tank asap. This test is occurring in a 125G 6ft tank. Ive tried to eliminate hostilities by keeping the clowns within same genre but it doesn't seem to matter. Best advice is to not mix if you don't want to see them die. And when they decide they don't like another fish it doesn't take long before they will kill the unlucky one.
Good luck,
Larry