But when polyculture, we should pay attention to the following points:

1. koi fish's body shape should be properly distinguished from polyculture to avoid competition or attack.

2. Snails, loaches, mussels and other creatures may have different habits, so it is necessary to ensure that they can survive and avoid mutual attack or competition.

3. koi fish and polyculture should be healthy and avoid cross-infection of diseases.

4. The water quality of the polyculture pond should be kept good to ensure the health of all living things.

5. The environmental conditions in the polyculture pond should be similar to the original environment of all living things to help them adapt to the new environment.

In the polyculture pond, there may be some interaction and competition between koi fish and other creatures. If any inadaptability or abnormal behavior is found, the water quality or environmental conditions should be adjusted in time to ensure the health of all living things.