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Silver pompano (Trachinotus blochii) is one of the major commodities of the aquaculture industry in Lampung. Silver pompano hatchery activities that still require natural feed, namely Brachionus sp. Brachionus plicatilis is a filter feeder that does not filter selectively all available feed, so an enrichment process is required so that natural feed reproduces with high nutritional content and is high in fatty acids (eicosapentaenoic acid [EPA] and decosahexaenoic acid [DHA]). This study aims to determine the best survival and growth of silver pompano larvae by feeding B. plicatilis enriched with EPA and DHA fatty acids derived from maggots black soldier fly (BSF). Five-day-old silver pompano larvae with a density of 20 larvae/tank in a 20 × 20 × 20 cm aquarium container. B. plicatilis was fed at a density of 13 ind/mL. Nannochloropsis salina was also given as additional feed at 300–400 cells/mL density. We gave B. plicatilis three times a day (05:00 am, 02:00 pm, and 9.00 pm) for 30 days of cultivation. The experimental treatments were A (no enrichment), B (100 ppm), C (300 ppm), D (500 ppm), and E (700 ppm). The conclusion of this study is the provision of EPA and DHA oil from maggot BSF with different doses of rotifer enrichment has a significant effect on the growth of silver pompano larvae. The results showed that the optimal dose of EPA and DHA oil was 300 ppm or 0.3 mL/L in treatment C with an average absolute length growth of 2.11 cm, and the survival rate reached 75%.

The objective of this study was to evaluate how the tank colours may change the effects of extreme temperature on the survival, growth, and quality of juvenile golden trevally (Gnathanodon speciosus). The experiment was set up with fifteen treatments of five tank colours (blue, red, yellow, grey, and white) and three temperatures (30°C, 32°C, 34°C) with three replications. Fish performance was assessed for four weeks. The results showed that tank colours and elevated temperatures affected the quality of golden trevally juveniles. The survival and growth rate of fish tend to decrease gradually, but the deformation rate of fish tended to increase in the order of tank colours: red, yellow > grey, blue, and white. The growth and survival rate of fish gradually decreased when the rearing temperature increased from 30°C to 34°C and this effect was independent of tank colors. Importantly, the deformation rate increased under elevated temperature, particularly in blue and white tanks with potential long-term effects. It is, therefore, not recommended to use blue and white tanks for rearing the golden trevally juveniles, particularly during extremely high temperatures from heatwave events.