"Three-opening" means that the aerator is opened at noon on a sunny day, the next morning on a cloudy day, and the continuous rainy midnight. "Two-off" means that the aerator is not to be used in the evening and at noon on a rainy day.

Three open

1 Start at noon on a sunny day

In the hot summer and autumn days, the stirring effect of the aerator can break the uneven vertical distribution of dissolved oxygen in the pond, convection the water in the upper and lower ponds, stir the large amount of supersaturated oxygen produced by the photosynthesis of the upper phytoplankton into the bottom layer, and promote the bottom organic matter Decompose to reduce or prevent the occurrence of fish floating heads in the early morning of the next day. Generally, it is better to start the machine for 1 to 3 hours at noon.

2Turn on the next morning on a cloudy day

In cloudy days, the upper layer of the pond has poor light intensity, phytoplankton produces less oxygen, and the dissolved oxygen in the pond water is not high, but the oxygen consumption factor is relatively increased. In the early morning of the next day, the supply of dissolved oxygen was insufficient. At this time, the aeration and aeration functions of the aerator can be fully used when the machine is turned on, which accelerates the dissipation of oxygen-consuming gases in the water and directly increases oxygen to avoid low peaks of dissolved oxygen in the pool water. The startup time is about 3 to 5 hours in the early morning, and usually starts until sunrise.

3 Start at midnight on continuous rainy days

Continuous rain, not only the photosynthesis of phytoplankton is weak, but also the wind is low, the pressure is low, and the oxygen consumption is high. Pond fish often float their heads in the middle of the night. Turning on at midnight can increase the dissolved oxygen to relieve the floating head. At this time, it will continue until sunrise after turning on. In addition, if there are many reasons such as water, fat and fish that may cause serious floating heads of the pond fish, it is necessary to start the machine before the floating heads to prevent the occurrence of "pan-pond" dead fish accidents.

Inseparable

1No power on in the evening

In the evening, the dissolved oxygen in the pond water is not too tight, and there is generally no need to start the machine. If it is turned on in the evening, it will not only have little effect, but will cause early convection and vertical mixing of the upper and lower water layers of the pond, increasing the oxygen-consuming water layer, forming oxygen debt, and even the dissolved oxygen in the water at dawn will reach a low peak, which will easily cause fish to float. Therefore, it is not suitable to boot in the evening.

2No power on at noon on rainy days

Because of the lack of light on cloudy and rainy days, the thermal layer formation of the pool water is not obvious, and the photosynthesis of phytoplankton is weak, and the dissolved oxygen in the surface water layer is not supersaturated. Turning on at this time not only can not increase the dissolved oxygen of the lower water, but also reduces the oxygen-making function of the upper phytoplankton, increases the oxygen-consuming water layer of the pond, accelerates the oxygen consumption rate of the lower layer, and easily causes fish floating heads, so it starts at noon There is no point in stirring the water.

This is the traditional "three openings and two non-opening", and the basis of judgment is also to control the start and stop of the aerator based on the diurnal variation of the dissolved oxygen in the still water pond. But how to judge the level of dissolved oxygen in the water? In the past, farmers relied on their own breeding experience. When to open aerators, how many aerators, and how long they were on, there was no scientific basis, so that the water Whether there is enough dissolved oxygen is also uncertain. Moreover, in order to ensure "sufficiency" of dissolved oxygen, the farmers have kept aeration opportunities running for a long time, which virtually increases the electricity bill.

However, the author believes that as the breeding density continues to increase, the increase in the water will play a more important role in the water mixer. In addition to the "three open and two non-open", the aerator should also pay attention to the long startup time on hot days and increase its water supply. Layer exchange ability plays a role in cooling and promoting food, and the boot time is short on cool days. Long boot time at midnight, short boot time at noon Wind is small, the boot time is long, and the wind is big, the boot time is short. The pond has a large amount of fertilization and a long startup time. Less fertilization in the pond, short start-up time