Koi are a member of the carp family and are generally quite robust fish. However, generations of inbreeding (to obtain the exact desired physical characteristics, such as colour, pattern, size and physical shape) means today’s Koi are genetically weaker than their ancestors. This inherent weakness makes them more susceptible to disease, which means you should take extra care when it comes to creating the perfect environment for your Koi.

Generally speaking, the two most important things we need to get right with Koi are water quality and the correct diet.

The Importance Of Water Quality

Poor water quality causes stress in Koi, which can put their already weakened immune systems under pressure. Parasitic and bacterial diseases are more prevalent in fish that are stressed. This is because stressed Koi produce less mucous, and it is this mucus that forms a protective, disinfectant barrier over their skin, helping to shield them against infection.

Optimal water quality means happy Koi, and happy Koi are stress-free! This means their immune systems are running at maximum efficiency, giving them their best chance against potentially life-threatening disease.

What Do We Mean By Optimal Water Quality?

The ideal water quality for happy Koi has a pH of between six and nine and has zero levels of ammonia and nitrates. Oxygen levels should be at a minimum of 6mg per litre, and there should ideally be no trace of the chemical elements commonly found in tap water. These include chlorine, copper, iron, lead and zinc.

“Harder” water is preferable to “soft,” although this is more difficult to control as it depends largely on where you live. Toxins have a more difficult time dissolving in hard water, and it also helps with osmoregulation, which is the process by which Koi regulate the fluid levels in their bodies.

Remember that the quality of the water is not always indicated by its clarity. A clear pond can be “bad” and a murky pond can be “good.” Green pond water is actually full of algae, which is fantastically beneficial for Koi.

Food Glorious Food

There are several high-quality brands of Koi food available and it is essential to use one of these and not be tempted to use a generic fish food. You’ve invested a lot of money stocking your Koi pond – now is not the time to economise by buying less expensive food! Koi food is specifically formulated to look after the fishes’ health, colour and growth, as well as the overall strength of their immune system.

A Diet For All Seasons

Koi are poikilothermic, which means their body temperature is determined by the temperature of the water. They, therefore, need a different diet in summer to the one they require in winter. In low temperatures, food passes through a Koi’s gut much more slowly than when the water is warmer. If it stays there too long, it starts to decay, making the fish very sick. It’s therefore essential to feed your Koi a low protein food during the winter, and a higher protein diet in the summer.

For more really helpful advice on taking care of your Koi, on how to design and install a Koi pond, or anything else to do with ponds or swimming pools, chat to the passionate pond and pool people at Pool Spa & Filtration Supplies.