Effects of background color and aeration on survival, growth performance, skin color change rate, and standard metabolic rate of low quality juvenile pot-bellied seahorses (Hippocampus abdominalis)

Physical environmental conditions commonly affect the survival and growth performance of cultured seahorses. In addition, due to the differences of broodstock seahorses in quality or physical status (e.g. difference in male’s brood pouch, genes or physical conditions), the quality of juveniles may vary greatly. Under these circumstances, the effects of environmental stressors on juvenile seahorses may become markedly pronounced. Investigating suitable physical environments to improve the survival of low quality juveniles is one of the important issues which need to be considered in seahorse culture. In the present study, we investigated the effects of tank color and aeration intensity on the growth, survival, standard metabolic rate and skin color change rate of the low quality juveniles of the pot-bellied seahorse , Hippocampus abdominalis . The results showed that the juveniles reared in black tank with gentle aeration intensity had the highest survival rate, better growth performance, higher skin color change rate, and lower standard metabolic rate (SMR). Therefore, black background color and gentle aeration are recommended for rearing the low quality H. abdominalis juveniles. • Juvenile pot-bellied seahorses reared in black tanks with gentle aeration exhibit better growth performance and higher survival rates. • Early juveniles of the pot-bellied seahorse reared in the black tank had higher skin color change rate. • The SMR of early pot-bellied seahorses reared in the black background with gentle aeration was lowest. • For culturing early juveniles of the pot-bellied seahorse, black background and gentle aeration are recommended.