Why do carp black pits need to be cleaned regularly? Why can't you catch any fish?

Some small black pits have poor self-purification ability of water bodies, and in addition, frequent fishing, a large amount of bait accumulates at the bottom of the pit. When the weather gets hot, the residual bait at the bottom of the pit will rot and deteriorate, and then the odor will be released at the bottom of the pit, destroying the water body, and the fish do not like to go to the bottom or open their mouths. In order to improve the water quality and increase the fish yield, it is necessary to put. There are too many fish in small black pits, and the fish are seriously deprived of oxygen

In some small black pits, if more fish are released and oxygen is not replenished in time, the fish will be deprived of oxygen. The more fish are stored in the pits, the more serious the oxygen will be, mainly because the pits are too small and there is too little water. In order to alleviate this situation, we can only reduce the fish storage, clear the pits on time and take them out. In order to improve the profitability, the recycling cost of large black pits is

Some large black pits are designed as bottom pot pits, and the amount of fish released is very large. Every time the fish is released, it is more than 1, kilograms, and the fish yield is generally controlled at around 6%, that is, 3%~4% of the fish is stored every fishing time. After a few fishes are released, the amount of fish stored in the pits will be very large. This kind of black pit generally does not stink at the bottom, nor does it suffer from severe hypoxia. The purpose of cleaning the pit is to fish out the fish, then sell it and directly recover the cost. Therefore, many large-scale black pit fishing grounds will clear the pits and catch fish on time. The weather is not suitable

Fish are very sensitive to the weather change, because the weather change will directly cause the change of water temperature and air pressure, which will affect the dissolved oxygen content in the water. Water temperature and oxygen are the environmental requirements for fish to survive. When the temperature is too high or too low, the temperature changes strongly, and the air pressure is low, it is not suitable to go out fishing. Try to go fishing when the weather continues to fluctuate. It is not allowed to find the water layer for fish to eat

In the same water body, different fish have different swimming layers under different climatic conditions. Under normal circumstances, grass carp, bream, silver carp and silver carp all like to move in the middle and upper layers of water; Crucian carp, carp, etc. like to move and find food in the middle and lower layers of water. With the change of weather and water regime, its swimming layer will change. Therefore, we should find the right swimming layer of fish according to the climatic conditions at that time. The fishing time is not sure. < P > As mentioned earlier, the weather has a great influence on fish, but this influence will not last long, because fish can't keep eating. Of course, it is only for crucian carp and carp that the weather is bad and the fish don't eat for a while. At this time, it is necessary to grasp the fishing time better. Theoretically speaking, it is good to fish in the morning and evening, but if it is treated in special circumstances, it is not ideal to catch fish in the morning and evening at a certain time.