Welcome to the SWF Boards...Couple things, an 8 inch Porky Puffer is a really large fish for a tank that small, I would not have anything else with him, the bioload from such a big eater is a ton....that Damsel is likely to become lunch very soon. Dried krill was the only thing my porky would eat at first, but you have to train him to eat other foods, try frozen shrimp, silversides, clams, squid etc. As far as the starfish, not really a major food source for puffers, but if he thinks its food, he will eat it....