Groupers, with ubiquitous distribution in warm and temperate marine waters, are highly valued for their flesh quality (Ottolenghi et al., 2004) and are intensively exploited in the coastal artisanal fishery resulting in them being over-fished (Morris et al., 2000;Sadovy, 2000). For alleviating the fishing pressure, farming of groupers commenced in the 1980s, driven by their organoleptic qualities, robustness under crowded conditions and rapid growth at elevated temperatures. Among the various grouper species existent in southeast Asia, orange-spotted grouper, Epinephelus coioides, with high market prices and demand, contributes significantly to the live fish trade. The species is euryhaline and eurythermal, and like other serranids, protogynous hermaphrodites.Triggered by the high market value of orange-spotted grouper and the sporadic supply of juveniles from the wild, broodstock development, induced breeding and seed production were initiated four decades back (Chen et al., 1977). Subsequently, natural spawning (Toledo et al., 1993;Yousif et al., 2016) year-round (Ranjan et al., 2017 was reported, albeit with low larval survival and inconsistent seed production (Rimmer & Glamuzina, 2019;Yousif et al., 2016).Despite the advancement in larviculture techniques for other marine finfish, heavy mortality during orange-spotted grouper larval production is common between three and 9 days after hatching.