ever since i downgraded tanks, my coral have shot up. my xenia has multiplied and each polyp has grown considerable in a short amount of time. my star polyps are spreading like mad. so down to the question part, will different colonies of star polyps sting, chemical, or otherwise attack each other? i have some really nice looking pink star polyps and i was wandering if i add a small colony of greens beside them, would that be a problem. im kinda looking for the 2 seperate colonies to mix around each other so that it might eventually look like one colony, i figure if i can grow a little on some crushed rubble, then glue the rubble spread out with the different colors. thanks for any help.