That isn't a tigerfish. Look at the caudal fin and the mouth.
I'll stand by my assessment. I've had many young and adult brycon. TFD's fish has caudal forks way too long to be a brycon. There's no hint of the dark center band or upper fork band that's seen in brycons. The pic doesn't allow a proper view of the head to make an absolute determination. However, the head appears to be more elongate than in the brycons I've had.
Also note that all of the species listed appear to have arrived from an african shipment. Brycon are south american.

