I have a smooth river back sting ray that has a 12 inch disk. We noticed two large bumps on his head and are not sure where they cam from or are...has anybody ever experienced this? He also has been barley eating. He with mouth the food but wont consume it. Weve tried garlic to help. His poop has also been a dark green, almost algae color. He is in a tank by himself. Any advide/info would be much appreciated!