WHY DOES MY GOLDFISH FLOAT AFTER EATING?
Floating goldfish post-eating is a common issue that results in an internet wormhole. Let’s get some facts straight:
Goldfish are Physostomous Fish
Yes, it’s a big word. What is means is that goldfish, like many other carp, have a pneumatic duct between their swim bladder and esophagus. It connects in between the cranial and caudal swim bladder.
Goldfish Like to Eat
Many goldfish eat like ravenous Golden Retrievers, sucking in floating food at the surface. In doing so, they inadvertently suck in extra air, resulting in added volume to their swim bladder. Additional air in the swim bladder results in a positively buoyant fish, aka a floaty fish.[...]