Goldfish, carp and crucian carp. The fish pond is 60 cm deep, and can support various types of koi fish, goldfish, carp and crucian carp, because they are all large freshwater fish and cold water fish, and it is no problem to mix them together, because their properties are the same, and they all take red worms and earthworms as their main food sources and are omnivorous fish. Cold-water fish is a kind of fish, mainly according to the requirements of fish for the living environment, especially the water temperature. When the water temperature is higher than 20 degrees, people cannot survive.