On Friday morning in my classroom before we started our class, my one goldfish- the feeder fish type that I have had probably for 3 years now, began to spaz out. He darted all around the tank and actually bumped into the sides and plants in the water. He then started to not be able to stay upright when he swam. My students said that he was dying. After a few seconds in floated down to the bottom of the tank and just lay there on its side. We all felt like we had just witnessed his death. A couple of the boys went over to look at him and noticed his eyes looked big, but yet he appeared to be still breathing. I figured once class was over, and they left the room I would remove the goldfish. Within 3 minutes of what we assumed was his dramatic death, he was back up swimming around as if nothing had ever happened to him. Before I left school I went and did a partial water change and his was alive and well at that point. Some of us were wondering was it like a stroke, heart attack, or choking on something. Rather curious if anyone has a possible answer to our miracle goldfish.

Just a guess: maybe he knocked himself out while he was thrashing through the tank. Maybe he had an itch that needed scratching and he just got knocked out for a bit.

Fish don't come in and out of consciousness. They're very fragile when it comes to their environment.

He could have gotten an air bubble in his belly.