In general, small fish can be kept in a bottle for about a year, and then injected with crystal oxygen and nutrient solution. Small fish can continue to live. In fact, it is difficult to achieve a life span of one year, because the fragile microecological balance in the bottle will soon be broken if the fish wants to grow up. If only this fish could live for two or three months. It must also be that the temperature and light are in an ideal state. If the temperature is too high or too low, the light is too weak or too strong, it will affect the growth of aquatic plants and destroy the balance. These fish either started or were poisoned by their own excrement.

① In order to better promote the oxygen exchange inside and outside the environmental protection bottle and prolong the natural life of the environmental protection bottle, the cork should be opened as much as possible. 2. Eco-bottles should be placed in a cool place indoors. Indoor scattered light is enough to maintain the growth of aquatic plants. It shouldn't be in the sun. The optimum growth temperature of ecological bottle is 18~22℃, and drastic temperature change is also easy to cause biological death. 4. Accidental death of natural creatures is a normal phenomenon. If aquatic organisms or plants in ecological bottles are found dead, they should be taken out in time to avoid polluting the water quality. If the water in the bottle evaporates, you can add "drinking water" to supplement it.

① Ecosystem includes producers, consumers and decomposers. The foundation of stability is the one-way flow of energy and the circulation of matter. As an energy source, sunlight maintains the "energy flow" of the ecological bottle. Among them, the ratio of the three is strict. For example, algae as producers absorb sunlight and carbon dioxide to produce oxygen and organic matter, small fish as consumers digest organic matter to release energy and waste, and bacteria as decomposers decompose waste into inorganic matter and carbon dioxide for algae ... and recycle them to form an ecosystem.

The key of ecological bottle is to keep the balance between matter and energy. The substances in the ecological bottle are certain, so it is necessary to ensure that the conversion ratio of each substance can just meet the needs of the organisms in the bottle. The balance of energy is based on and reflected in the balance of matter.