Why are shading nets used in sea cucumber farming?

1. Sea Cucumbers Are Highly Sensitive to Water Temperature

 Sea cucumbers are highly sensitive to water temperature changes. Their suitable growth temperature is generally between 8-20°C. When water temperature exceeds 20°C, they gradually enter aestivation. If the temperature stays above 25°C for a prolonged period, mass mortality occurs — what farmers call "pond collapse." Summer heat is one of the biggest risks in sea cucumber farming.

2. Shade Nets Effectively Lower Water Temperature

 Installing shade nets above ponds is the most direct and effective way to reduce temperature. Shade nets block direct sunlight and can lower pond water temperature by 3-5°C. Don't underestimate these few degrees — for sea cucumbers, it's the difference between life and death. Once the temperature drops, sea cucumbers can safely get through the hot season without mass mortality.

3. Extending the Growth Period and Increasing Yield

 In ponds with shade nets, sea cucumbers enter aestivation later and become active earlier in autumn, gaining nearly one extra month of growth compared to ponds without shade nets. This extra month means larger sizes, higher yields, and better returns. For farmers, this is a tangible economic benefit.

4. Inhibiting Harmful Algae and Improving Water Quality

 During hot seasons, ponds are prone to outbreaks of harmful algae such as blue-green algae. When these algae die, they pollute the bottom sediment and affect sea cucumber habitats. Shade nets effectively inhibit harmful algae growth, stabilize pH, and keep water clean. When the bottom environment improves, survival rates and quality naturally follow.

5. Practical Tips for Installing Shade Nets

 When installing shade nets, the frame height should be 2-2.5 meters, with coverage of about 50% of the pond. Leave ventilation gaps to avoid heat buildup. The distance between the net and water surface should exceed 1 meter to ensure air circulation. Install the nets 2-3 days before the hot season arrives, and prepare the frames in advance. Avoid excessive coverage, as it may affect phytoplankton photosynthesis.

6. Conclusion

 Using shade nets in sea cucumber farming is not optional — it's a key measure for survival, production, and profit during hot seasons. A shade net lowers water temperature and protects the entire pond of sea cucumbers. For farmers, this investment is worth every penny.