There’s nothing like homemade food…is there?

Why do we so often prefer to give our koi homemade food? Is it distrust “fat cat” food companies or does home-prepared diets have a psychological benefit for koi enthusiasts who need to give what they see as extra care?

The feeding of koi has specific aims and objectives in terms of maintenance and growth. These are measures totally separate from those for farm animals since longevity, vitality, skin colouration and sustainability of optimum water quality are the main sought-after goals. Therefore, in many ways the nutritional feats expected of koi food often exceeds those of both human food and farm animal feed.

Koi feeding aims to consistently give enjoyment to both the koi and its owner. However, eating well by itself is no guarantee of good nutrition because what may fill koi does not necessarily nourish its cells and tissues. Over the long term, sub-optimal nutrition may predispose koi to early aging and degenerative disease since its nutritional state is associated with several of the body’s defense mechanisms against disease. Optimum nutrition assures optimum tissue integrity, an increased immune response, and ability to detoxify metabolites emanating from a challenge, and other benefits that alleviates stress.

There is no single nutrient that is capable of satisfying all the nutrient requirements of koi. These nutrient requirements can only be completely met by blending various raw materials through balanced formulations. In order to achieve the blend that offers the best possible “nutritional insurance”, all ingredients are being selected to provide all necessary nutrients in a highly palatable form. Further objectives of koi food formulation aim to:

• enhance the natural skin colours of the fish, and
• reduce the impact of unutilized nutrients on the aquatic environment.

Although homemade foods aim to achieve these objectives it often fail to do so due to the limited availability of certain essential ingredients. The result is huge amounts of undigested nutrients that foul the water and create optimum conditions for disease. Even if food is stabilized with gelatin mixtures it is most often unbalanced and nutritional deficiencies develop already at an early stage. Another good example is the popular recommendation to soak cat food in water prior to feeding it to koi. As a herbivore, a koi is not suppose to eat cat food (carnivorous). Koi has a longer simple digestive tract without a stomach and needs much longer time to handle the longer (“perhaps the only results will be that cat food will make their whiskers grow…”). Furthermore, soaking food prior to feeding cause leaching of highly digestible nutrients to the water, diluting it’s nutrient-supply even further. Any approach that seeks various sources of home-prepared food to make up a balanced diet and meet the daily nutrient requirements of koi is a very complex approach and most often impossible. Knowledge on the nutritional value of ingredients is essential - it is the combination of nutrients (and not ingredients) that make up a completely balanced koi food. Rather find a reliable supplier of koi food that offers an extended range of food so that “variation” should only mean supplying the appropriate food for the appropriate life stage of your koi.

It is true that commercial koi food seems to be more expensive and less “fresh” than homemade food and that label claims can be quite confusing, but it offer more than just nutrients:

• The unique manufacturing process of koi food results in a highly digestible product with an excellent water stability and buoyancy.
• It destroys anti-nutritional components and many harmful parasites and bacteria in koi food rendering it a more hygiene and safe product.
• Food companies often have a direct line to their nutritionist to serve as an free information backup to their customers to advise on good nutrition practice.

Although food may be defined as “any substance that is capable of nourishing a living being”, a balanced complete food is the only one actually capable doing the job right! So, do not attempt to give your koi other than balanced foods without first consulting with a qualified nutritionist or vet who is well versed in fish nutrition. Supplementing their diet with home-made foods is not advised as it may unbalance an otherwise balanced diet, and many nutrient reactions can result in a reduced availability of specific nutrients. Rather than looking for some “magic” food formula, quality of feed should be carefully controlled, and sensible feeding practices should be adopted. Then all the fish really require is good attention and a healthy environment.

Lourens de Wet