新手养什么比较挣钱？情感共鸣。冬天养鱼技巧，鱼越冬注意事项！一、选好池塘；二、合理放养；三、投饵施肥；四、水体管控。二、鱼越冬注意事项：1. 越冬在我国北方地区，多数鱼需要越冬，而温州文成则多数温水性鱼类是不需要越冬的，可将进行鱼屯养，即冬季池塘的载鱼量可达平时的2—3倍，可选择适当深一些池进行屯养，不屯养也可以。在长江流域的大部分地区，winter是进行捕获和放养的好时机，water temperature低，适合于fish的运输和分养。

而热带fish或带fish在文成需越winter，即water temperature下限在12—15℃以上的fish类，可在greenhouse内或plastic大棚内越winter，供heat可用地heat、burn coal、burn diesel oil。需越winter's fish其cost相对要高，而且越winter期间的water quality control and disease prevention也是关键环节。

3. 1米水深的pool water temperature与air temperature difference要根据seasons、cold air降temperature速度和持续时间以及是否rain来考虑，一般来说water temperature与air temperature相比有一个“滞后” effect，即air temperature上升和下降比water temperature要快（水体比热大）。Summer time温度出现在气温中，而Winter time气温也出现在气温中；Summer time一定深度的pool有warm layer，即上下temperature不同（白天上高下低，在晚上渐趋一致），Winter time cold结冰时，low layer water Temperature仍然有4℃。Winter month from December to January in the process of cooling down when surface water Temperature drops, cold water sinks to the bottom, but once it reaches 4℃, further cooling will not cause the water to sink again.

Therefore, the difference between air and water temperatures is mainly determined by the duration of cooling; as long as this period is prolonged, so does the overall drop in pool water Temperature. However, rain or heavy rain can accelerate this process.

The above are for everyone introduced "over wintering techniques for fish and over-wintering precautions!" Fish cultivation is a process that starts from raising small fish to maturity through careful nurturing; what matters most in this process is not just earning high profits but also learning more about it every day!