eating habits

Question
i have been using tetramin flakes (the standard brown/yellow container). Lately, i noticed my fish are anxious when they know im gonna feed them (they rush to the top of the tank, etc). but when i drop some flakes in for the most part they spit a lot of it out, or approach the food and maybe nibble it but dont eat it. then the food lands at the bottom of the tank and dirties up the gravel. sometimes i see the angel fish pecking at the bottom but never really eating much. i feed them once a day. should i try a different brand? if so, can you suggest one? ive been using this tetramin all my life, ive never seen this problem before.

Answer
I have had a similar problem with some flake foods.  I had fish who didn't like the red flakes.  Switch to a granule or pellet food and try switching gradually.  Try feeding less as well.  Most people tend to overfeed their fish, feed two small meals a day.  One about 20 Minutes after you turn the lights on in the morning and one about 20 minutes before you turn off the lights at night.