Is your goldfish sick if the corner of its tail turned red then fell off?

Yes, it is likely that your goldfish is sick if the corner of its tail turned red and then fell off.

Fin rot is a common bacterial infection in goldfish that can cause the following symptoms:

* Redness and inflammation of the fins

* Fin erosion and fraying

* Loss of fin tissue

* White or cloudy mucus on the fins

Causes of fin rot:

* Poor water quality (high ammonia, nitrates, or nitrites)

* Overcrowding

* Injury

* Stress

Treatment:

* Improve water quality: Perform a partial water change and use a water conditioner to remove chlorine and chloramine.

* Treat with antibiotics: A veterinarian can prescribe antibiotics specifically for fin rot.

* Salt baths: Short, shallow salt baths can help disinfect the fins and reduce inflammation.

Prevention:

* Maintain good water quality.

* Avoid overcrowding.

* Provide a stress-free environment.

It is important to note that:

* Self-treatment can be dangerous and ineffective.

* It is always best to consult with a veterinarian for proper diagnosis and treatment.

If you notice any signs of fin rot, it is important to act quickly to prevent further damage and infection.