Enlargement technique of humpback grouper (Cromileptes altivelis) with floating nets cage

Grouper became an important export commodity especially to Hong Kong, Japan, Singapore and China. National and international market demand for humpback grouper which continues to increase causes overfishing in the sea. Humpback grouper is cultivated by using floating net cages to reduce dependence on nature. The working methods used in the study are direct observation to obtain primary and secondary data. The results have been carried out, the technique of enlarging humpback grouper begins with the preparation of floating net cages. Every cage checked and installed nets. The breedstock that have been spreaded are fed trash fish once a day in the morning. Grading is done once a month to reduce fish cannibalism levels. The water temperature in cages ranges from 30-30.6 C, salinity 34-35 ppt, pH 8.09-8.2 and dissolved oxygen 5.0-5.3 ppm. Prevention of pests and diseases is carried out by changing the net periodically, cleaning cages, and dipping with fresh water. SR value of 50%, FCR 3.27, and growth rate of 0.4167 grams. Humpback Grouper in Floating nets cage is not best for growth but is able to optimize production.