OMC, a couple more comments I might add to the great advice you've already received. AM 500 should be the correct, but depending on the size of the fish you got, you may have some that aren't big enough to eat it yet. In a few months, they will be so don't get discouraged if they just peck at it for a while. They'll quickly grow into it, and you can adjust feedings as needed.
I also pass on the 15 minute rule, but I do it because of my prevailing wind. Sprkplug said it perfectly, "Let them tell you what they want".
