You can refer to what you said and my suggestion. A relatively stable small ecological circle must have the most basic food chain. As the lowest part of the food chain, aquatic plants are essential. As long as you raise aquatic plants well, you don't have to worry too much. Aquatic plants can not only purify water quality, but also release oxygen to increase the oxygen content in water, and can also be used as food for fish.
Cultivation of aquatic plants. -I feed aquatic plants. Specifically, I spread a layer of coarse sand on the bottom of the fish pond, then put some goose warm stones and press the aquatic plants under the small stones. It should be easy to find aquatic plants in the lake in the park. Pick a greener fish, and it will be better if your pond is bigger. Keep aquatic plants in the sun every day. If you can't sunbathe, you can use lights instead. At present, the best effect is halogen lamp. Aquatic plants use carbon dioxide (exhaled by fish) and nutrients (excreta of fish) to metabolize and grow under photosynthesis, and at the same time release oxygen. When aquatic plants carry out photosynthesis, you will see small bubbles in the water, which are oxygen released by aquatic plants. Also pay attention to the ratio of fish to aquatic plants. If they lose their balance, one of them will die.
After a long time, fish tanks and small stones will turn into green Mao Mao. This is actually green algae, and it is recommended not to clean it. Green algae also release oxygen through photosynthesis, which has no effect on water quality and fish. Fish farming needs water first, and the best water is the so-called green water and green algae.
1 water. Tap water is generally used for water, but there is residual liquid chlorine in tap water. In this case, you must dry the water for three days to completely evaporate the chlorine in the water. Don't change the water too often. Generally, change the water when the turbid silk is slippery. To change water, leave the original water in 1/3 or 1/4.
2. Temperature-I like cold water fish, and there is no special requirement for water temperature. It should be noted that when changing water, the temperature of fresh water should be consistent with the water temperature of fish farming, otherwise the fish will easily catch a cold and not adapt to the water temperature, leading to the death of the fish. The solution is to put dry water and fish tank together and keep the same water temperature.
3. Oxygenation-If there is an oxygenator, add oxygen regularly for a period of time every day. If not, keep some live aquatic plants in the fish tank.
4. Feeding-If you feed the fish and don't feed the fish for ten days, the fish won't starve to death. Usually feed it once every two to three days, and don't put too much at a time. According to the number of fish, it's almost enough to feed too much, and the fish will definitely die.
If you can do the above, I believe that ordinary cold-water fish will have no problem under normal circumstances.