If you are new to owning and caring for Koi, you don’t want to learn the hard way that Koi can become sick. This doesn’t have to be the case. There are preventative measures you can take to avoid stress by the Koi.
What is Stress?
Stress is what occurs when there is an extended period of chemical or environmental changes. Fish can adapt well to short-term pressure such as escaping predatory attack or the vibration of a loud noise. When those types of events take place, it generally takes the Koi a few hours to recover. But when that stress continues for a long period of time, it takes a toll on the Koi’s immune system. A weakened immune systems means the Koi are more vulnerable to disease and can even lead to death.
Five Ways to Avoid Stressing your Koi
1. Do not expose Koi to any sudden changes in water temperature
Koi are very hearty fish and can tolerate a vast range of temperatures, but they do not do well with sudden changes in temperature. When they are exposed to sudden temperature changes it becomes too stressful for them. Much like you will do upon arrival of your Koi fish, always remember the acclimatization process when transferring your Koi into new water.
2. Do not overstock your pond
Much like us humans, it is very stressful for Koi to live in an overcrowded environment. The more crowded the pond, the more fish that are producing waste. Unless your pond has filters big enough to handle the excess waste, the water quality will most assuredly suffer as ammonia and nitrite levels rise when water isn’t properly filtered. When the pond is overcrowded, the Koi will also begin to compete for food.
If you are faced with the challenge of an overcrowded pond, you need to come up with a solution rather quickly. The best thing to do is to sell some of the Koi or build a bigger pond. Other alternatives are reducing the feed amount or partially changing the water in order to dilute the ammonia build up.
3. Protect Koi from predators
It’s ingrained in Koi to protect themselves if they feel they are in any danger. The very sight of any predator can cause immense stress to Koi. Do everything possible to protect your Koi from being eaten external predators like heron and other wild or domesticated animals. This may mean installing an electric fence, or motion-activated sprinklers, or netting of the pond and so on. Take care to design your pond with the Koi’s maximum safety in mind. Netting is the most effective method of protection. Unfortunately, it’s also the least unattractive.
4. Maintain the water quality
This may be one of the most important tips to remember to avoid stressing the Koi. You should regularly check that chlorine levels are low and the water is highly oxygenated. You can also buy water-testing kits that indicate the water’s ammonia level, nitrite level and pH level. The ideal pH for Koi is 7.5. They can tolerate a stable pH level between 6.7 and 8.1, but it is very dangerous if the pH varies by more than 0.5 within a 24-hour period. Remember, chemical and temperature changes in water lead to stress for the Koi.
5. Never have less than 2 Koi in a pond or tank
Koi fish do not like being on their own; they are sociable creatures. Always make sure there are more than one fish in any container. If you have to temporarily remove a Koi because it is ill, it is still advised to put the sick Koi in a tank with at least one other Koi to keep it company and alleviate some of the stress associated with sickness.