three giant black pacu fishes in an aquarium behind glass. huge exotic tropical tambaqui from south america at the exposition

actinopterygii amazon america animal aquaculture aquarium background behind black blackfinned bottom brazil cachama characiformes closeup colossoma complex dnipro dnu exotic exposition fauna fish floating freshwater gamitana giant glass huge large macropomum national nature pacu river serrasalmidae south swim tambaqui tank three tropical ukraine underwater university view water wild wildlife zoo