Fish farming is a college question, you need to learn too much knowledge.
Water temperature: Fish are ectothermic animals, and the fish body does not have the function of regulating its own body temperature, and it changes completely in accordance with the temperature changes of the surrounding environment.
Softness and hardness: The hardness of water is also important for the growth and reproduction of tropical fish. Generally, most of the tap water in major and medium-sized cities in my country is river or reservoir water, and its hardness is suitable for the growth of most tropical fish. .