Can fancy goldfish live with black skirt tetras?

Verdict
No

No. Fancy goldfish and black skirt tetras should not share a tank. Black skirt tetras nip fins, and the long fins of fancy goldfish are an easy target.

Fancy goldfishFancy goldfish65–74°F · pH 7–8 Black skirt tetraBlack skirt tetra70–80°F · pH 6–7.5

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Both: 70–74°Fancy goldfish 65–74°Black skirt tetra 70–80°
The green band is the temperature range both can live in.
456789Both: 7–7.5Fancy goldfish 7–8Black skirt tetra 6–7.5
The green band is the pH both tolerate.

Size to scale

Fancy goldfish · 6 inBlack skirt tetra · 2.5 in0"1"2"3"4"5"6"
Adult length in an aquarium. A fish can swallow anything that fits in its mouth, roughly a third to half its own length for predators.

Care at a glance

Fancy goldfishBlack skirt tetra
Temperature65–74 °F70–80 °F
pH7–86–7.5
Adult size6.0 in2.5 in
Minimum tank30 gal15 gal
TemperamentPeacefulSemi-aggressive
Swims atAll levelsMiddle
GroupAlone or in pairsGroups of 6+
DietOmnivoreOmnivore

Better tank mates for fancy goldfish

All fancy goldfish tank mates

Better tank mates for black skirt tetras

All black skirt tetra tank mates

Questions

Can fancy goldfish live with black skirt tetras?

No. Fancy goldfish and black skirt tetras should not share a tank. Black skirt tetras nip fins, and the long fins of fancy goldfish are an easy target.

What temperature suits both fancy goldfish and black skirt tetras?

70–74 °F. Fancy goldfish need 65–74 °F, black skirt tetras need 70–80 °F.

What size tank do fancy goldfish and black skirt tetras need together?

At least 30 gal, set by the fancy goldfish. Add space for each extra fish.