Arowana can live with koi in the same pond. However, there are a few important factors to consider in order to ensure the cohabitation is successful.
1. Size compatibility: It is crucial to keep the size of the fish in mind. Arowanas are known to be aggressive and territorial, especially when they feel threatened or when their territory is encroached upon. Therefore, it is recommended to keep the arowana smaller than the koi, or at least similar in size. This reduces the chances of the arowana attacking the koi.
2. Proper pond size: Both arowanas and koi require ample space to swim and thrive. The pond should be large enough to accommodate the size of both fish comfortably. A crowded pond can lead to stress and aggression, so ensure sufficient space for each fish to establish their territory.
3. Pond design: The pond should be designed in a way that provides hiding spots and visual barriers for the fish. This helps to reduce the chances of aggression and allows the fish to have their own space. Adding plants, rocks, or other decorations can create hiding places and break the line of sight between the fish.
4. Water quality: Both arowanas and koi thrive in clean and well-maintained water conditions. Regular water testing and maintenance are essential to prevent any health issues. Ensure proper filtration, regular water changes, and monitoring of ammonia, nitrite, and nitrate levels. Maintaining good water quality will help keep both fish healthy and stress-free.
5. Feeding considerations: Arowanas are carnivorous, while koi are omnivorous. It is important to provide a varied diet that meets the nutritional needs of both species. Feeding them separately or using feeding rings can help ensure each fish gets the appropriate food without competition or aggression.
6. Monitoring behavior: Observing the behavior of the fish is crucial. Look out for signs of aggression, such as chasing, fin nipping, or excessive hiding. If any aggression is observed, it may be necessary to separate the fish temporarily or provide additional hiding spots.
7. Sufficient oxygenation: Both arowanas and koi require well-oxygenated water. Adequate aeration and circulation should be provided in the pond to maintain oxygen levels. This is particularly important during hot summer months when oxygen levels can drop.
It is worth mentioning that while it is possible for arowanas and koi to live together peacefully, there is always a level of risk involved. Some individuals may be more aggressive or territorial than others, so it is crucial to carefully monitor the behavior and wellbeing of both fish. In case of any signs of aggression or stress, it may be necessary to separate them to ensure their safety.