Koi are the most common fish we see through our veterinary service. The majority of issues in koi are secondary to poor water quality. We understand that in drought prone areas, doing your regular water changes can be difficult. With limited maintenance, stress from poor water quality often leads to secondary diseases involving bacteria, parasites and fungi.

If you are having an issue with your koi, check your water quality FIRST. If your parameters are not within range, it is time for a water change. Always use a liquid-based test kit that has been purchased within the last year. The expiration date is only for the store shelves.

Ammonia</= 0.1 mg/L
Nitrite0 mg/L
Nitrate<80 mg/L
kH>100 mg/L
gH>100 mg/L

If your parameters are within range, how many fish are affected? Is it just one fish or more than one? If only one fish is acting sick, move it to your quarantine system. If you do not have a quarantine system, you should get one set up or have one ready.

One of the most common issues we see in koi are gonadal sarcomas. These are space-occupying tumors most common in female koi that cause a prolonged pregnancy appearance. It is important that these tumors are caught early. If you have a fish that looks like the image below for a long period of time, or has an asymmetrical belly, they need to be screened ASAP. Screening is a painless process performed with ultrasound under anesthesia.

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If you require further assistance, please call our office at (831) 278-1081. Appointments cannot be made over our website or email.