You may have just acquired a new ornamental marine fish and are having difficulty in starting it to eat. Anything you can get into the fish at that point is a 'good food.' For more on getting new acquisitions to eat, see this post: http://www.reefland.com/forum/marine...-eat-tips.html

Now the the fish is eating, or maybe you've acquired a fish that is only eating a certain type (like pellets or flake) of food, it is time to get it eating the right kinds of foods. Being well informed about what is and isn't the 'right food' by reading this post: Feeding Marine Fish and Fish Nutrition you are knowledgeable and informed about what nutritional needs this fish has. Yeah. Right. Read those posts again.

Don't forget how important 'presentation' is in the feeding of your marine fish: Food Presentation

Now that you've read all the above, I can add some information that can work to get the eating fish to eat the right kinds of foods.

Marine fish get into habits. Why does the fish act excited when the person who feeds it enters the room?

The basics of getting a fish to eat what it should eat is based upon (simply) what the fish considers to be good eating. If it looks good, moves good, smells good, the right size/shape, tastes good, then the fish will eat it.

When a fish is in a rut, it is primarily relying on the taste. Next is the smell. It won't eat something of the 'wrong' size. Once size is addressed, then the hobbyist just needs to fool the fish into eating something else.

The ways of fooling (without going into detail) include, but aren't limited to:
1. Mixing what it eats with what it doesn't eat, slowly reducing what you don't want it to eat;
2. Adding a flavor (garlic) to the food it likes (at first very little then more up to 1%) until the fish gets used to that new flavor and smell, then add garlic to the food it should eat and follow number 1.;
3. Using a dither fish that wants to eat the food the other fish doesn't want to eat (competition can be a strong incentive);
4. Take the food it eats and grind it up--liquefy it. Then gel some. Then feed it the gelled formula until it gets used to that, then mix in the food it should eat into a new gel formula, slowly lowering the other food (that is, use the food it likes as flavoring and smell, but get the fish used to a different shape); and
5. If the fish will eat two things, then form combinations of the above 4.

Humans can use their imagination, fish can't. Handling a fish is easier than handling a two-year old human child that doesn't want to eat its veggies. Only, you can't threaten the fish. So the human has to be smarter.

DON'T EVEN THINK OF STARVING YOUR FISH to get it to eat something else. Fish can't be starved to eating something. Starvation just adds stress and that is another reason not to eat!