The fire fish is most likely being put in place by the new clown. Don't worry too much. The best way to get food to the little guys in crevices and toward the bottom and back of the tank is to make a mix of food and instead of dropping the food onto the surface of the water, make the food look like it's snowing. Swish the food around. The current produced from the swishing will allow food particles to reach hidden areas where other animals may be.
Try thawed out frozen foods like krill, brine shrimp, cyclopseze are a favorite among the fish, mysis shrimp, and squid. Also, check your water quality. This is a new fish adding more ammonia and waste to the system. You just want to make sure ther isn't an ammonia spike occuring that may be affecting appetite. You can also benefit from feeding the fish garlic soaked food about once a week or every other week...especially when a new fish is introduced. Garlic is an appetite stimilant and also a method of preventing external parasites from latching onto the fish. Just as garlic works with dogs and cats with fleas and us with mosquitos, it wards off ich. Doesn't kill the little buggers but they don't like the aroma of garlic and are reluctant to eat on a fish that tastes like it too.
We, as a people, know so much more about outer space than we do about our own oceans. This lack of knowledge can very well spell the dangers that lay in wait for us.
The oceans surely would swallow us before a rock comes down to smite the planet of it's life.