Goldfish can live for an average of 10 to 15 years, with some fish living up to 30 years if they are taken care of correctly. Unfortunately, many new fish owners lack the knowledge and skills required to care for their goldfish properly and so the fish die prematurely. Fish owners can determine whether or not a goldfish is still alive by observing their fish's behavior and actions.
Dead Goldfish Don't Swim
Observe your goldfish carefully. If your fish is floating at the very top of the tank, he might be dead or he might be sick. If he is lying at the bottom of the tank in the substrate, he may also be dead. Observe your fish for any signs of life, including the movement of his gills as he breathes. If your fish is still moving, he may be sick but he isn't dead.
If you are still unsure as to whether your fish is alive or dead, touch him gently. The net you use to scoop fish out of your aquarium may be ideal for this task. If your fish swims away or moves, he is not dead. If he does not move, he may very well be dead. Go ahead and use the net to scoop him out of the tank.
Physical Appearance of a Dead Goldfish
Look at your fish very carefully. Observe whether his eyes appear alive or if they have turned gray or sunken into his head. If your fish's eyes are gray or sunken in, he is deceased and most likely has been for several hours.
Look at the color of your goldfish's skin. If it has turned white, he is starting to decompose. Some types of fish may eat other fish. If your non-moving goldfish appears to have been chewed on or partially eaten by the other fish in your tank, he is dead.
Your Goldfish Has Gone Missing
Sometimes the only indicator you have that a fish may have died is that you can not locate it inside your tank. If your tank does not have a lid on it, check the area around the tank to see if your fish may have jumped out of the tank. If your tank does have a lid, there are several places you need to look for your missing fish:
Check the bottom of the tank Check the corners of the tank Open the hood and inspect the area around the filter Check the filter inlets Check under your tank decor Check in and around your plants
In most cases, your fish has not left your tank but may be dead somewhere in the tank. In some cases, the corpse may be consumed by the other fish before you are able to locate it.
Disposing of Dead Goldfish
Remove the dead fish from your tank immediately so that any illnesses the fish may have been suffering from will not spread and the decomposing corpse cannot contaminate the tank water. It is not a good idea to flush a dead goldfish down the toilet. It can contaminate your water system as well as block your plumbing if the fish is too large. Burial is an effective way to get rid of your dead fish, as is placing it in the trash enclosed in a plastic baggie.