When it comes to keeping goldfish in cohabitation with other fish, the following points need to be noted:

Choose Appropriate Fish Species for Cohabitation:
Angelfish: Angelfish have a gentle temperament. When cohabiting with goldfish, they require sufficient space and a steady supply of oxygen, and the water temperature should be kept constant.
Guppies: Since goldfish and guppies have different requirements for water temperature and there is a significant difference in their body sizes, it is not recommended to keep them in cohabitation.
Molly Fish: Molly fish are small and gentle. They get along well with goldfish, neither competing for food nor being bullied.
Blood Parrot Cichlids: They are relatively large in size and require a large fish tank with sufficient space and a constant-temperature environment.
Tetra Fish: They are small in size. When cohabiting with goldfish, they will neither compete for food nor be bullied. They need an ample supply of oxygen and a constant water temperature.
Platy Fish: They require an ample supply of oxygen and a constant-temperature environment.
Kissing Fish: They are small in size. When choosing fish species for cohabitation, it is necessary to select those with a similar body size, and the water temperature should be kept constant.
Preparations Before Cohabitation:
Health Check: Ensure that all fish are healthy to avoid cohabiting fish with diseases.
Fasting Preparation: Fast the fish for a few days before cohabitation to empty their intestines and reduce potential troubles during cohabitation.
Disinfection and Disease Prevention: Use potassium permanganate or oxytetracycline for disinfection to prevent infections.
Environmental Requirements During Cohabitation:
Space and Density: Ensure that the fish tank has enough space to avoid overcrowding and maintain an appropriate stocking density.
Oxygen Supply: Install an oxygen pump to ensure an ample supply of oxygen in the water, especially for fish species that require a large amount of oxygen.
Water Temperature Control: Use a heating rod to keep the water temperature constant and avoid significant fluctuations in the water temperature.