Outline of juvenile production Seed production usually begins with the catch of adult sea cucumbers from the sea in January. These animals are then reared for about three months. Propagation of periphitic diatoms on corrugated plates is also started in February. In April, the induction of spawning of brood stocks is carried out, and larvae are cultured to a viable stage for about two weeks. These animals are shipped out to be released directly in the sea from July to August.
Light penetration is controlled by a black mesh sheet placed over the tanks.
About 70 per cent of sunlight is shut-off on fine days and 50 per cent during cloudy or rainy days. The second step is washing with high-pressure sea water and reversing the plates once or twice a week. This method can significantly remove the larger diatoms that grow on the plates, thus making the smaller and highly adhesive diatoms dominant, which accelerates the propagation rate of the diatoms. The larvae gradually increase in size through the 9th day. After that, body size falls to about 500 m m, and they grow up to doliolaria larvae.