Effects of salinity and feed on growth and survival rate of juvenile payangka (Ophieleotris aporos)

Payangka fish (Ophieleotris aporos, Blekeer) in Lake Tondano belong to the suborder Gobioidea, which generally migrates amphidromously. In its development, this fish is thought to have experienced isolation by a hydroelectric dam, which may have caused this fish to have adapted to fully live in freshwater. In order to understand this fish, hence, this research was conducted, which aimed to determine growth, feed efficiency, feed conversion ratio, and survival rate using different salinity treatments and feed types. This study used juveniles (2-3 cm) with an average weight of 0.2 grams, which were maintained for 50 days. The salinity treatments given were 0, 10, and 20 ppt, as well as artificial feed and silkworm treatments. This study was designed according to a factorial experiment in a completely randomised design. The results showed that absolute growth ranged from 1.44 to 1.97 grams, specific growth was 4.18 to 4.74%, relative growth was 706.98 to 970.79%, feed efficiency value was 52.82 to 57.07%, feed conversion ratio was 0.31 to 0.41, and survival rate was 66.67 to 86.67%. It was concluded that the best condition for forthis fish is at the salinity of 10 ppt and fed by silkworms. In addition, juvenile fish still have amphidromous characteristics where they are able to live and grow in a salinity range of 0 ppt to 20 ppt and are adaptive to artificial feed (pellets) and natural feed (silkworms). This indicates that this fish has the potential to be used in aquaculture, which could help sustain its population in aquatic ecosystems.