When my TSN was 10" I fed him feeders and pellets small pieces of meat left over from dinner. problem at the time was his tank mate was a much more aggressive eater and was outgrowing him. One day he started eating algae wafers which the RTC HATED and believe it or not he caught up to the RTC in size. My guy is about 17" - 18" now and He eats Massavore every night only about 5-6 pellets, 2x per week they get a dozen med gold fish feeders to share. also will eat anything I am eating - chicken - Turkey - pork. It's so hard with what to feed all my fish, and I always worry about overfeeding. I try to judge by what others feed and what a healthy fish should look like. when my guys were smaller they used to get bigger belly's, they just don't seem to eat like that any more. They don't act like their starving and look good.
my LFS received an adoption last year of a 2 foot RTC and the woman said she fed it lunch meat only, I heard on MFK that someone feeds their fish dog food. go figure.