Koi Carp exhibit a range of brilliant colours. It's the spectacular colouration which distinguishes Koi and that endears so many people to keep these particular fish. Whether you're interesting in competing for a prize-winner or simply want your specimens to look at their best, it is important that you promote excellent colour in your fish. To do this you must ensure that they enjoy the right environment and are fuelled with the correct diet. An unhealthy or stressed Koi will quickly show signs and theirbeauty will fade.
The Healthy Pond
Poor water quality is the primary cause of most health issues in Koi. The fish will quickly become stressed and the strength of their colours will be affected. Clear water does not necessarily mean good quality water and so you should test your pond regularly to ensure that you are providing the best environment for your fish so that they may thrive. Koi colouration can also fade if the water becomes too hot, so monitor your water temperature closely during the summer months. Definitely provide shade if your pond is likely to reach 85 degrees or more. At this temperature your fish's digestive system is far less efficient. Water quality can be impacted because oxygenation is reduced and beneficial bacteria become less efficient at processing waste. Take care not to shade your pond for too long as Koi require a measure of sunlight to exhibit the finest colours. Whilst the strength of colour that your Koi display is partly down to genetics, even the finest specimens will begin to fade in poor conditions.
Koi Food
It is imperative that your fish receive a nutritious diet both for colour enhancement and general good health. To ensure this you should select high quality foods to provide a balanced diet and during the primary growth period, give foods which include colour enhancers. This will be when the water temperature is at least 70 degrees (generally June to early September). You must capitalise on the opportunity to enhance the colour of your fish at this time of year. Revert to a lower protein diet free of colour enhancers at other times.
Colour Enhancers in Koi Food
Many Koi foods contain natural colour enhancers. It is carotenoids which work their magic on colour and these are found in many Koi food ingredients including shrimp, krill, paprika, marigold flower and spirulina. Spirulina is a tropical plant algae thatis extremely high in protein. Indeed it boasts the highest protein content of any natural food. You should take care not to over feed colour enhancers as they can lead to discolouration of white areas of your Koi. These could take on a yellow, brown or green tinge. In this scenario the discolouration is caused by the effect that carotenoids have on light rather than because your fish's pigmentation has actually changed. White skin cannot feature red pigmentation as it does not have the necessary red chromatophores.
Artificial Colour Enhancers
It is also possible to feed your Koi artificial colour enhancers. Astaxanthin and Canthaxanthin are powerful sources of colour and must be provided in carefully measured doses. You should seek expert advice before using either of these.