Quarantine separates incoming koi from the established population while their condition is assessed. It reduces introduction risk; it cannot certify every fish free of infection. Plan the protocol before purchasing, using a fully prepared separate system.
Define the Arrival Group
Record supplier, arrival date, individual identity, transport history, and any testing or treatment. Keep unrelated arrivals separate. Adding a new fish to an existing quarantine group creates a new exposure and changes the observation plan; do not keep counting from the first arrival without reviewing that change.
Keep Water and Equipment Separate
Use dedicated nets, bowls, hoses, and cleaning tools. Prevent splashes, drainage, and wet equipment from carrying material to another system. Care for established fish before a suspect group, then follow appropriate cleaning and hygiene procedures. Sharing a filter loop defeats separation.
Observe Under Suitable Conditions
Check breathing, swimming, skin, appetite when feeding is appropriate, water results, and equipment every day. Calendar length alone is insufficient: temperature, exposure history, developing signs, and interventions affect the plan. Aquatic Veterinary Services describes a four-to-six-week observation period in its general guidance; ask a fish veterinarian how that applies to the actual arrivals rather than treating it as a universal release date.
Further reading: Aquatic Veterinary Services: Quarantine.
Avoid Automatic Preventive Treatments
Routine salt, heating, dips, and mixed medicines do not provide a disease-free guarantee. They can alter observations or create additional problems. If signs develop, document them and obtain a diagnosis-led plan. Record products, doses directed by the professional or label, dates, and follow-up requirements.
Release on Reviewed Criteria
- Water and life support are stable in both systems.
- No unresolved concerning signs or unexplained losses remain.
- Any investigation, treatment, and follow-up have been completed as directed.
- The group history is traceable and any new exposure has been considered.
Use the quarantine overview and arrival monitoring alongside this protocol.