Hippocampus guttulatus is a European seahorse species whose breeding in captivity started in 2006 in the frame of “Proyecto Hippocampus. Until recently, attempts to develop a rearing methodology resulted in low survivals during early development mainly due to mortalities associated with swimbladder hyperinflation. In order to improve survival and growth rates, the most appropriate rearing conditions concerning zootechnics (type of aquaria, aeration level), physical factors (photoperiod regime, temperature) and feeding (type/quality of prey, prey digestibility and digestive capabilities) were assessed. The results achieved allowed for the first time the closure of the life cycle of H. guttulatus, the incorporation of the species into the aquarium trade and the definition of a standard procedure (pseudoKreisel aquaria, strong aeration, 19-20ºC, 16L:8D photoperiod regime and copepods + Artemia diet) for the successful rearing of the species providing high survivals (70-90% at 30 DAR) and growth rates.