What fish are raised in fish ponds will not improve water quality. After all, fish still have to be excreted in water. However, some filter-feeding or herbivorous fish can clean up excessive algae and other aquatic plants in water, thus maintaining water quality, such as silver carp, bighead carp and grass carp. If you really want to improve the environment of fish ponds, you still need to raise some plants with water purification ability.

1. Grass carp: Grass carp is usually the main fish intercropping, belonging to one of the four major fish, and it is also one of the few herbivorous fish. It is widely distributed in China, and can be seen in rivers and lakes in plain areas. Usually, it likes to move in the middle and lower layers of water bodies or places with more aquatic plants, and its temperament is lively and fast.

2. Silver carp: Silver carp will not have any conflict with other fish because it is an upper fish and its feeding habit is filter feeding. In addition, it can clean up some plankton and algae, thus improving the water environment. However, its economic value is not high, and it will generally be raised a lot if it is interplanted.

3. Carp: Carp belongs to benthic fish and is also a common freshwater fish in China. It lives at the bottom, so it can eat some food scattered under the water, thus avoiding the deterioration of the bottom material, which is also beneficial to the environment of fish ponds, and it is not difficult to raise.