I've had my red Crowntail (Firefly) for 2 and a half years now... He's not a very active fish anymore... usually finds his spot on a leaf in his 3 gal bowl and chills there till I feed him and then he's all over the food... then back to his spot. Am I assuming correctly that this is normal behavior for an older fish to get lethargic and chill in his recliner all day? He's never had any sickness that I've been aware of and otherwise seems like a healthy fish.
I recently added a snail to the bowl that's the size of an olive that he flares his fins at.