Can black ghost knives live with gold barbs?

Verdict

No. Black ghost knives and gold barbs should not share a tank. An adult black ghost knife eats fish that fit in its mouth, and at 3 inches gold barbs do.

Black ghost knife73–82°F · pH 6–8

Gold barb64–75°F · pH 6–8

What to watch

Deal breakerAn adult black ghost knife eats fish that fit in its mouth, and at 3 inches gold barbs do.
Watch outBlack ghost knives grow to 15 inches and need 125 gallons, far more than a tank set up for gold barbs.

What works

Both are fine at 73–75°F.
pH 6–8 suits both.
They use different parts of the tank: black ghost knives the bottom, gold barbs the mid.

Water side by side

The green band is the temperature range both can live in.

The green band is the pH both tolerate.

Size to scale

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

	Black ghost knife	Gold barb
Temperature	73–82 °F	64–75 °F
pH	6–8	6–8
Adult size	15.0 in	3.0 in
Minimum tank	125 gal	20 gal
Temperament	Semi-aggressive	Peaceful
Swims at	Bottom	Middle
Group	One per tank	Groups of 6+
Diet	Carnivore	Omnivore

Better tank mates for black ghost knives

All black ghost knife tank mates

Better tank mates for gold barbs

All gold barb tank mates

Questions

Can black ghost knives live with gold barbs?

No. Black ghost knives and gold barbs should not share a tank. An adult black ghost knife eats fish that fit in its mouth, and at 3 inches gold barbs do.

What temperature suits both black ghost knives and gold barbs?

73–75 °F. Black ghost knives need 73–82 °F, gold barbs need 64–75 °F.

What size tank do black ghost knives and gold barbs need together?

At least 125 gal, set by the black ghost knife. Add space for each extra fish.