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Fish Health, Quarantine and Biosecurity

Breeding systems concentrate fish, feeding and handling. That makes prevention, observation and clean equipment more important than routine medication.

Freshwater focusWelfare-firstUpdated July 2026

Quarantine new fish

Use a separate, cycled system and dedicated nets or siphons. Observe appetite, swimming, breathing, skin and waste before mixing populations.

Separate sick fish promptly

Isolation may limit spread and makes observation easier. It does not replace diagnosis.

Do not medicate by habit

Treatments can harm fish, fry, invertebrates or biological filters when the problem is misidentified or the dose is wrong.

Clean between groups

Remove organic debris and disinfect appropriate equipment according to safe product instructions. Never mix cleaning chemicals.

Find qualified help

A fish veterinarian or aquatic animal health professional is the right source for diagnosis, humane euthanasia and prescription treatment.

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