Nijssen's cory

About

A small armored catfish from the soft, acidic blackwaters of the Rio Negro basin in South America, Corydoras nijsseni carries a pattern that draws comparisons to more widely known species like C. adolfoi, sitting on a rounded-snouted body reminiscent of C. elegans. Like all corydoras, it wears two rows of bony plates along its flanks in place of conventional scales, and those sharp pectoral fin spines are worth keeping in mind whenever you need to move the fish. They catch in nets easily and can give you a genuine poke. This species is as peaceful as corys come, and makes a natural fit in softwater community tanks alongside small characins, dwarf cichlids, and other gentle fish. Avoid anything large or boisterous. Group size matters enormously with this species. A lone cory or a pair will spend most of its time hiding, but a group of six or more becomes noticeably bolder and more active throughout the day. You will occasionally see them dart to the surface for a gulp of air; this is a normal physiological behavior, not a distress signal, though more frequent surface visits can hint at declining water quality. Substrate cleanliness is genuinely important, as dirty conditions lead to barbel erosion. Breeding is achievable with patience, and the classic cory T-position spawning behavior is fascinating to observe. With proper care, these fish can live well into their teens.