Selling aquarium fish treats is a win/win/win scenario.

Good for fish. While a good quality "staple" flake or pellet food will be scientifically formulated to meet the dietary requirements of a typical mix of tropical fish, many hobbyists find that including a few treats on a regular basis results in a healthier, more colorful collection. There are many possible reasons for this. In some cases, the fish might be so different in dietary needs from the average that staple foods are actually shortchanging them in some important nutrient. For other fish, standard flake or pellet foods might be too unnatural to trigger an active feeding response, and they simply will eat greater quantities if offered alternatives. Finally, I'm no fish psychologist (tried it once, but the Oscar kept flopping off the couch), but many fish appear to simply be "happier" when feasting greedily on a sheet of dried algae or chunk of frozen brine shrimp.

Unlike those marketed to us Homo sapiens, fish treats are not just deep-fried empty calories chock full of artificial flavors and colors. Most are nutritious, delicious foods that just happen to entice aquarium fish into a state of gluttony. Some contain natural color enhancers, and others like frozen mysid shrimp have very high levels of healthful HUFA (Highly Unsaturated Fatty Acids) which seem to play a large part in the survival of some difficult species like seahorses.

Good for fishkeepers. I ...