Goldfish Problems

3 goldfish with bubbles

A variety of goldfish problems will occur while you care for your fish. Careful attention for unusual goldfish behavior can be an early way to detect problems.


Below are reviews of some of the most common problems that occur and relatively simple treatment measures.

Unusual Behavior

  1. Symptom: Fish darting back and forth through the tank.

    Diagnosis: Probable Poisoning

    More information on Goldfish Poisoning.
  2. Symptom: Fish only at surface, hanging around filter outlet, gasping for air.

    Diagnosis: Hypoxia, a lack of oxygen.

    More information on Goldfish Hypoxia.
  3. Symptom: Breathing rapidly, trying to jump out of tank, shooting through the water.

    Diagnosis: Acidosis or Alkalosis of water

    More information on Goldfish Acidosis.

Goldfish Illnesses

See Goldfish Illnesses Page.

Over Feeding

What do you do if you realize you accidently overfed your fish? Or accidently dumped a bunch of food in the tank?

If there is any remaining food after 5 minutes of feeding attempt to remove it. If it is floating on the surface use a net to skim it off the top. If it is on the rocks in the bottom use a hose to 'vacuum' it up.

Remove excess food IMMEDIATELY as your water quality will decrease very quickly. This is the number one cause of death for your goldfish.

More information on Optimal Goldfish Diet.

Not Eating

What should you do if your goldfish are not eating?

If your goldfish are feeding poorly or not at all check the following....

  1. You may be feeding them incorrect food. More information on correct feeding of goldfish
  2. Water temperature may be too low. For optimal water temperature for your type of goldfish see individual types of goldfish.
  3. Poor water quality. You may have problems with pH, oxygen, nitrite and ammonia levels.
  4. There may be more dominant fish in the tank eating the food.
  5. There may be an illness...check fish for signs of illness. More information on Goldfish Illnesses.

Change in Color

Is it a problem if my goldfish are changing color?

No. It is normal for a goldfish to change color over time.

A speckled fish will usually lose it's speckles and be a uniform color of red, orange or gold.

Usually the back and belly are the last places to change color.

fish scales

Bottom Feeding

My goldfish picks up gravel and then spits it out is this unusual goldfish behavior?

This is absolutely normal and nothing to be concerned about. Goldfish are known to be bottom feeders. What they are doing is checking the gravel for food.

If you have other goldfish problems check our Common Questions about Goldfish.

Return to top of Goldfish Problems page.





›› Goldfish Problems