What aspects need attention in winter greenhouse farming of soft-shelled turtles?

At present, the primary task for soft-shelled turtle farmers is how to farm safely and get through the winter, laying the foundation for pond division farming in early spring. For this reason, the author introduces valuable experience in greenhouse soft-shelled turtle farming as follows, for the reference of fellow farmers:

The first point is that the temperature must be kept stable, with no major changes. The soft-shelled turtle (trionyx) is a semi-aquatic poikilothermic animal and is very sensitive to changes in environmental temperature. Temperatures that are too high or too low, or sudden drastic changes in temperature, are all detrimental to the survival, growth and reproduction of soft-shelled turtles, especially the young turtles and juvenile turtles that are the mainstay of current farming. The most suitable water temperature for soft-shelled turtle growth is 28-32°C; beyond this range, the feeding and growth of soft-shelled turtles will be affected. The daily change in water temperature is best kept within 1-2°C, and preferably not more than 3°C. Drastic water temperature changes make it difficult for young turtles to carry out adaptive physiological regulation, and the body's metabolic processes are prone to disorder, more easily leading to the occurrence of diseases such as colds. In overwintering farming, lighting is easily overlooked. After the beginning of winter, the sunshine duration is relatively short, so light can be appropriately supplemented inside the winter greenhouse. According to relevant research data, supplemental lighting significantly increases the growth rate of soft-shelled turtles and can also increase the survival rate. Many farmers currently overlook this point, and it is suggested that they might as well give it a try. In winter, temperature and humidity should also be properly controlled. If the farmer's greenhouse is well sealed, ventilation can be appropriately increased. For a north-south oriented greenhouse, it is suggested that the ventilation flow on the south side can be increased, and slightly less on the north side; for an east-west oriented greenhouse, the ventilation volume can be increased on both the east and west sides. At noon when the light is stronger, oxygen can be appropriately added for 1-2 hours to promote the discharge of carbon dioxide from the lower water layer, which is beneficial to the growth of young turtles and juvenile turtles. A humidity below 40% is relatively ideal. It is easier to control before the Beginning of Spring, and after the Beginning of Spring the humidity will rise, so pay attention to ventilation and the reasonable control of humidity. In winter, water quality management must be stricter than in other seasons. The water quality indicator most prone to deterioration in winter greenhouses is ammonia nitrogen content, which is generally ideal when controlled below 0.3ppm. If ammonia nitrogen is too high, soft-shelled turtles are prone to gastrointestinal discomfort and to diseases such as rotten skin, rotten legs and rotten mouth. In terms of controlling water color, transparency and pH, it is best to keep the water color yellow-green. If the water color is too dark, use an appropriate amount of quicklime for slight adjustment, then put in an appropriate amount of photosynthetic bacteria and Bacillus, and appropriately turn on the aerator at noon to cultivate the water color. In this way, the dissolved oxygen in the water body will be relatively ideal, and it will be more beneficial to the growth of young turtles and juvenile turtles. Overwintering young turtles and juvenile turtles are small in size and poor in resistance. In addition to ensuring good feeding, greenhouse farming should also appropriately add compound multivitamins, microbial preparations, and Chinese herbal medicines for protecting the liver and promoting bile secretion, to protect gastrointestinal and liver-gallbladder functions, making them a guarantee for improving the survival rate and growth speed.