
Bleeding Heart Tetra
Megalamphodus erythrostigma
- Care level
- Intermediate
- Adult size
- 6 cm
- Minimum tank
- 81 litres
- Temperature
- 21–28 °C
Species profile
Gymnocorymbus ternetzi
Common names: Black Skirt Tetra, Black Widow Tetra, Petticoat Tetra

A deep-bodied, hardy tetra from South America with a dark, flowing rear body. It is easy to keep, but needs a large group to keep fin nipping under control.
A deep, laterally flattened body with two dark vertical bars behind the head, and a dark rear body with fan-like fins. Colour fades to grey in older fish.
The tall body shape and dark rear are distinctive. Long-finned, white, and artificially coloured forms are sold under related names, and dyed fish should be avoided.
Males are slimmer and smaller, with more pointed dorsal and anal fins. Females have deeper, rounder bodies.
Provide open swimming space with some planting and robust filtration. A larger group needs more length than a typical small tetra setup.
Active and generally peaceful in a large group, though individuals can chase or nip when numbers are low.
Keep at least 12. A larger group is the best way to reduce fin nipping.
Not territorial, but pecking orders form in the group.
Suitable with similar-sized barbs, tetras, danios, loaches, and corydoras. Avoid bettas, fancy guppies, and angelfish, whose long fins attract nipping.
Very adaptable. Avoid sudden changes, and keep nitrate low with regular water changes.
An unfussy omnivore that eats most flakes, granules, and frozen foods.
Regular feeding of varied foods helps keep the group settled.
Adhesive eggs are spawned in a group or in pairs in a separate, dim tank. Remove adults once eggs appear, because they eat them. Eggs hatch in 18 to 36 hours.
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