Head & Tail Light Tetra (Hemigrammus ocellifer)

Hemigrammus ocellifer has been a hobby fixture since the early 1900s, one of the tetras that helped establish the whole idea of a schooling centerpiece fish long before neons showed up. The reflective spots at both ends, a guanine patch on the head and a matching one at the tail base, aren't decorative extras, they're the same light-scattering iridophore trick every other flashy tetra on this list relies on, just placed at the two spots you'd naturally look first. Easy, old-school, and still a genuinely good school.

Care level: Easy · Temperament: Peaceful, shoaling · Max size: ~1.75" · Min tank: 15 gal · Diet: Omnivore, flake/micro-pellet