Killifish

About

Found in the temporary pools and seasonal wetlands of southern Brazil, Austrolebias adloffi is what's known as an annual killifish. A fish whose wild populations live, breed, and die within a single rainy season. The eggs are laid in the substrate and left to develop through the dry months, hatching when rains return and refill the pools. In the aquarium this translates to a fascinating but demanding keeping experience: despite being labeled beginner in terms of aggression and basic husbandry awareness, this species is genuinely tricky to maintain long-term and is really best suited to keepers who have done their homework. Breeding is a rewarding challenge. Eggs are deposited in soft substrate and require several months of dry incubation before they hatch. Adults are compact fish, staying well under two inches, and are carnivorous, preferring live or frozen meaty foods. The short lifespan is simply part of the deal with annual killifish. You're not neglecting them if they fade after a year or two, that's just their biology. If you enjoy species-focused projects and don't mind managing egg incubation, this little fish offers a genuinely unusual window into one of nature's more extreme life history strategies.