Evaluation of the Effect of Various Substrates on the Attachment of Juvenile Brown Mussel (Mytilopsis adamsi)

Brown mussel (Mytilopsis adamsi) is a potential alternative feed for lobster and crustacean aquaculture in Indonesia, with a balanced nutritional content of 13.29% protein and 80.30% water content, and does not compete with human food needs. This study was conducted because brown mussels are not consumed by humans so they can be concentrated as lobster feed without competing food sources. Cultivating brown mussels is expected to increase lobster productivity in Indonesia and provide consistent fresh feed for cultured lobsters. The development of brown mussels as lobster feed is also encouraged by the Ministry of Marine Affairs and Fisheries (KKP) to overcome the problem of inconsistent feed supply and improve feed quality for lobsters. This study aimed to assess the effect of four types of substrates (80% paranet, PE rope, white net, and paris cloth) on the attachment of juvenile brown mussels for 30 days at BPBL West Lombok, using a completely randomized design with 6 replicates. The results showed that PE rope had the highest attachment density in the water column (1.62 fish/cm2) and at the bottom of the container (6.91 fish/cm2). The absolute growth rate was recorded in white netting (860 µm for AP length and 1630.17 µm for DV), while the highest specific growth rate was found in paris cloth for AP (0.154%/day) and PE rope for DV (0.186%/day). It can be concluded that the study showed that PE rope was the best substrate in terms of density. White Net excelled in the absolute growth of brown mussel juveniles. Fabric stood out for AP length-specific growth rate, while rope performed best for DV-specific growth rate. The substrate at the bottom of the container consistently gave better results than that in the water column. Further research is recommended to assess the effect of varying attachment density on other substrate types, as well as longer rearing duration.