I've never had one, so you are definitely more experienced in caring for one, but you can find multiple videos on YouTube like this.They're not like groupers at all. I've kept both. Groupers are MUCH more aggressive feeders than comets/ marine bettas. Anything that fits in a groupers' mouth is a gonner. Comets also have a large mouth but are usually content with eating 2-3 pieces of mysis or 2-3 pellets in a day, they eat super slowly and tend to stare at food for a while before actually eating it. Plus they never move.