Why do Koi (and Goldfish) Change Color? Colin – Sunbury, OH
You’ve now created the perfect pond habitat and begun to add fish. Multiple trips to the pond store scanning the tank to find just the perfect one to bring home. Some have spots, some red, some orange with black streaks. At least you’ve found the perfect one, black and white pattern with orange freckles on the face. You make your purchase and carefully introduce your new friend to the pond. Everything is going great until one day a few months later you notice that those freckles disappeared and the perfect pattern is changing to white. What happened? Did the fear of the heron turn him white as a ghost? Is there something you did wrong? Luckily, most of the time it’s nothing too serious. Let investigate a few possible causes.
Sun exposure: If you are in a climate where you experience a cold winter and your koi have been hiding out in your pond waiting for spring you may notice your koi are a little lighter in color once the spring time thaw sets in. This is common because koi do not receive a lot of exposure to the sun over the winter months. Once they get back into the routine and the sun begins to shine this color will usually return.
Genetics: Most koi come from parents that were not identical so the same rules apply. Some coloration is dominant and some recessive. This could also change with time the same way your hair color changes. Someone born with red hair may turn blonde or brown as they grow older. This is just a natural part of growing up.
Stress: Stress factors such as predators, parasites, water chemistry or water quality may affect coloration. A quick change in pH due to overwhelming organics or over population would cause a stressful environment which may cause a color change. Be sure to test your water, address water quality issues if necessary or treat the pond with pond salt, water conditioner or fish disease control. Watch your fish for behavior clues to determine if they are stressed.
Food: What type of food do they eat? Inexpensive bulk food may not contain as many vitamins and nutrients which may affect coloration. This does not necessarily mean the fish are unhealthy but they may not be receiving enough vitamins to support their color. Try feeding them food such as Pond Logic® Growth & Color fish food, which supports coloration or even include fruits and vegetables such as oranges. Koi will love the citrus and this could greatly enhance their color.
Once you’ve addressed all these possibilities sit back, relax and enjoy your koi. The color may have changed but their playful personality will still be the same!
POND TALK: Have you ever had your koi change color?