The absence of scales on goldfish can be caused by a variety of reasons. Here are the common causes and corresponding solutions:
1. Dropsy (Pinecone Disease)
Cause: Dropsy is a disease caused by bacterial infection. It will lead to the gradual shedding of the goldfish's scales, and in severe cases, the goldfish may lose all its scales completely.
Solution: Use furacilin powder for a medicated bath once a day for 20 to 30 minutes, and continue this treatment for about 7 days. This can effectively relieve the symptoms.
2. Water Quality Issues
Cause: Poor water quality or abnormal water temperature (such as being too low or changing abruptly) can cause the goldfish's scales to fall off, and may even trigger the phenomenon of "exploding scales" (where scales stick out).
Solution: Change the water regularly to keep the water quality clean. Keep the water temperature above 25°C and avoid drastic changes in water temperature.
3. Physical Injury or Fighting
Cause: When goldfish fight with other fish in the fish tank or are hit by something, it may cause the scales to fall off.
Solution: Isolate the injured goldfish to prevent further harm, and apply anti-inflammatory medicine to the wound to promote healing.
4. Parasite Infection
Cause: Parasite infections (such as Saprolegnia) can corrode the scales of goldfish, resulting in the scales falling off.
Solution: Use potassium permanganate or oxytetracycline for a medicated bath to remove the parasites and prevent the spread of the infection.
5. Overcrowded Stocking
Cause: Having too many fish in the fish tank can cause goldfish to collide with each other while swimming. Long-term friction will lead to the loss of scales.
Solution: Reduce the stocking density to provide enough space for the goldfish to move around.
6. Genetic Mutation or Disease
Cause: In extremely rare cases, goldfish may have no scales due to genetic mutations or congenital ichthyosis.
Solution: This situation usually cannot be completely cured. It is necessary to pay attention to the water quality and the breeding environment to avoid further health problems.
Preventive Measures
Regularly check the water quality and keep the fish tank clean.
Avoid keeping aggressive fish species together with goldfish.
Provide suitable water temperature and sufficient oxygen.
If the goldfish's scale loss is severe or accompanied by other abnormal symptoms, it is recommended to consult a professional veterinarian or an expert in ornamental fish in a timely manner and take targeted treatment measures.