I'm an amateur fish lover. Before I learned how to properly care for fish, I unfortunately went through multiple goldfish.
From this experiance, I learned that some goldfish a day or two before their death would swim to the bottom of the tank and stay stationary in few positions. They may swim up when feeding time came around or when the aquarium was tapped. However, they mainly stayed in one spot at the bottom of the aquarium.
Lately, I've seen this sort of behaviour from a goldfish I've cared for successfuly for 3-4 weeks now. Sometimes when I feed him I notice he barfs up the fish flake and eats it again.
I have one fish in my tank and I try not to overfeed. I feed 1/4-1/2 a flake several times a day.
What does this strange behaviour mean? Especially the staying at the bottom of the tank? The tank water is not clouded, it is exposed to the air, and doesn't reek. I think it's been a week since I've changed his water and the tank is constantly aerated with a pump.
What signal is the fish trying to tell me?