i haven't tried to put them (dorado and armatus) together but dont think they mix well. Have got multiple atfs in range of sizes with 3 armatus in the upper size range. atfs tend to hover, then make single stroke dashes every now and then. The armatus have what i call a sidestep or pary. dorados movement is constant and causes unrest/stress for a fish that reacts, such as an armatus. I think over time, at best the armatus would move to a side area, and dorados would dominate the tank, which is fine i suppose if that's an agreeable outcome.
my odoes by comparison dont care if other fish bump into them, which is one reason why i think they go ok with dorados. when the new tank is done, i've decided to change plans to keep the atf/armatus/barracuda cohab seperate from the dorados.
my group of 7 D's are doing fine. I think DB just trade the big aggressive one out for smaller D's. Or get more, or put them in a smaller tank - both options giving the effect of a denser "shoal". I've noticed with other shoaling fish, big tank, not enough fish, and they either get aggressive or scared.
have kept non-asian arrow with dorados and atf with out issues. so long as sizes are such that the arrow wouldn't make a swipe at tank mates.
oh one thing to add... those armatus grow annoyingly quick and appears rate of aggression grows at similar rates. i think it's been about 3 months and the largest armatus has gone from 2-3inches long and less than an inch tall to 8-9 inches long and 2 inches tall closing in on my largest goliath just under a ft. I've had the goliath for about a year and it's only grown roughly 2-3 inches. Hoping the growth spurt grinds to a halt soon or may have incompatable sizes to deal with.
rays are cool, have yet to try them.
good luck with your experiment. just never know what may work. so many variables.
