The growth and survival rate of the larvae of the sunu grouper (Plectropomus leopardus) in different temperatures

The sunu grouper, known as the starch grouper, is one of Indonesia's leading export commodities of marine culture. Temperature is an environmental factor that directly affects fish life. Temperature fluctuations affect the hatchability of the eggs. Water temperatures in the often-changing cultivation medium can produce egg hatching rates ranging from 60 - 70%. The growth stage where the sunu grouper fish larvae become seeds lasts for 45 - 55 days at a water temperature of 27 - 29°C. This study was conducted with the aim of determining the optimum temperature of the development of the early stages of larvae (D0 - D7) for sunu. This research was conducted at Universitas Airlangga Laboratory PSDKU Banyuwangi between May and October 2017. The test material consisted of the eggs of sunu grouper obtained from Balai Besar Riset Budidaya Laut dan Penyuluhan Perikanan Bali. The method used in the implementation of this research was an experimental design that was Randomized Completely (RAL). The treatment consisted of one factor, temperature, and 4 treatments (26, 28, 30, 32°C) repeated 5 times. The results showed that the optimum temperature for the larvae of sunu was in at 30°C with a HR value of 99%, a growth length of 0.96 mm and an SR of 23%.