There are literally dozens of very similar Corydoras species, so I don't have a definite identification of these 3 Cories (data in table is for C. sodalis, the closest match). But it doesn't really matter, since most Cories do well in the same water conditions and have very similar behavior. This tank is quite appropriate for them, having lots of grassy plants and sandy gravel which they just love to poke into with their sensitive barbels. When keeping Cories it's important not to use sharp-edged gravel because it can damage their barbels.