Mexican Tetra

About

The Mexican tetra (Astyanax fasciatus) is one of the more widespread characins in the Americas, turning up in slow-moving streams, rivers, and still-water habitats from Mexico all the way down to Argentina. In the wild it is an opportunist, picking off smaller fish and invertebrates alongside plant matter and just about anything else edible that crosses its path. That omnivorous boldness carries straight into the aquarium. This is not a gentle community tetra you can pair with anything smaller than itself. It will make a meal of smaller tankmates and can nip at fins given the chance. At four to five inches as an adult, it has real presence in the water, and a group of them needs decent space to move and establish their own order. The body is silvery with a faint lateral band that becomes more defined depending on lighting and mood. Care sits comfortably at an intermediate level. Not because the fish is fragile, but because its temperament demands some thought when stocking. It tolerates a broad range of water conditions and is not especially demanding on that front. Given the right companions and enough room, it is an active, long-lived fish that holds its own in a larger community setup.