for about a week or two one of my red devils have been fighting with my salvini over the castle i have in the tank, so the other day i looked in the tank and noticed 2 or my 3 red devils where in the castle and the salvini was swimming around so i take it as the rd won, but mym question is is it possible that i might ahve a pair of RD's? being that only 2 of my 3 stick together eerywhere in teh tank?