Today I would like to talk about something not solely related to koi, but much more general. During my travels I don’t just observe pond fish, my visits also involve looking into a lot of aquariums. I often notice some very slim fish and when I ask, the owners tell me that they feed their fish at least three times a day.
Of course it goes without saying that the bigger the fish, the longer it may take to see the consequences of incorrect feeding. In our ponds too fish can become socialised with fish which have totally different nutritional requirements and which eat at different pace. This is one of the first reasons why fish can suffer from malnourishment. Also some fish are shy and some are quite cheeky. If you socialise them in a relatively narrow area, the shy fish will become smaller and slimmer, and in the long term malnourished. Again these fish “lag” behind the brisk and stronger fish as regards their immune system and defences and they are potentially more prone to illness. On the other side of the coin there are the different kinds of food. Of course, we know that there are omnivores, plant eaters (herbivores) and even carnivores amongst the fish. The fish’s diet needs to be adapted according to the fish’s requirements. If you feed a naze or a grass carp protein-rich food, they will probably eat it, but their digestive tract is not equipped for this kind of nutrition and in the long run this will result in deficiency symptoms.