The sex ratio in spawning can affect the efficiency and success of hatchery activities because sex ratio in spawning affects the number of eggs, the degree of fertilization, and the degree of hatching of eggs. Until now, there is limited research conducted in Corydoras paleatus fish spawning thus this study aims to determine differences in the reproductive performance of C. paleatus with different male sex ratios. This study uses three treatments, which are the ratio of fish male and female (1:1), (2:1), and (3:1). Each treatment uses one female fish. The vessel used in fish spawning is an aquarium with a size of 50 × 25 × 30 cm3. Spawning lasts for seven days and eggs are collected every day at 08.00. The number of eggs and larvae produced was not significantly different between treatments. Larvae produced by C. paleatus were 2,154 fish or 538 fish per female per week. The ratio (1:1) was considered an appropriate ratio in spawning C. paleatus fish because it has a high efficiency value.

Indonesia has a very high aquatic biodiversity, including local fish scattered in several areas. Currently, these resources are decreasing and even threatened with extinction if not noticing the environmental balance factor. Natural damages to the aquatic environment and increased fishing activity can cause the fish population and diversity to decline, even threatening the extinction of certain types of fish. Puntius ophoides is a commodity that has not yet developed its culture technology, so efforts are needed to investigate its reproductive biological aspects to encourage the culture development and maintain its sustainability level. The purpose of this study was to evaluate the effectiveness of PMSG hormone on the gonadal maturation pattern of this fish. This study used a completely randomized design (CRD) with four treatments and three replications, namely: 0 IU/kg, 5 IU/kg, 10 IU/kg, and 15 IU/kg body weight. The results showed that PMSG treatment at 10-15 IU/kg obtained the best performance compared to other treatments. PMSG hormone treatments could increase the gonadosomatic index (GSI) value by 15% compared to the control treatment. Increased hepatosomatic index (HSI) value was also shown at the end of the study with an average IHS value of 2%. This means that the PMSG hormone affects the vitellogenin production in the liver.