I have never owned an ATF of any kind but from what I understand of them they are very different then Dorado personality wise. I think the only way to get Armatus and Dorado to get along would be to dump Redelin in the tank when WCs are done. The Dorado would have to be slowed down somehow. Their activity level is high enough to drive any fish to commit harmful acts towards them. Very similar to people that talk non stop, sometimes you just want to silence them. In the fish world the only way to make an annoying non stop moving fish stop moving is to do what Armatus do best... Run those fangs into things. The effects of these 2 fish in the same tank is like tequila. 12 hours together and it takes weeks to make things right with all parties involved.