Cadet Blue Blenny is one of the most beautiful fish you will ever see. This fish is a beautiful blue color with a light blue stripe down its back. These fish have a very sharp dorsal fin and a very long, thin tail. These fish are very active and love to play. These fish are very healthy and will grow to a size of about 10 inches. These fish are a great choice for those who are looking for a beautiful fish that is healthy and active.