i want to know if its a good idea too add a blue dolphin to my tank. I have a 75G tank with 8 yellow labs in it right now. The labs are about 1 1/4 inches, and the blue dolphin i want too add is already 4-5 inches. Would this difference is size be a problem? i don't want the dolphin to kill any of my labs. Also I've been told that the dolphin's do better pair's, would a 75G be big enough for 2? what do you guys think? good idea or not.