I have a new tank its 28"18"25" don't know what size it is

[jonah h2o]

. Hydrolycus armatus I think there's a couple of different species with the same nick name I just know it was called a sabertooth Tetra When I was a kid and bought one at a local fish shop

those get pretty big.
bucktooth tetras are pretty cool though, they're like mini piranhas they swim in a pack and are aggressive