Black Ghost Knife Fish - Wild Meta River 8cm

Black Ghost Knife Fish - Wild Meta River

For the experienced aquarists chasing a true oddball fish, the black ghost knife is a must-have species. Ghost Knives have long been a mascot for oddball fish species and are usually captive-bred in large ponds for the aquarium trade. Finding wild-caught black ghost knives is a very rare occurrence and they can offer a unique challenge as they adapt to captive life whilst also showing true ghost knife behavior. These individual fish come from the meta river off South America and will be a really great consideration for a biotope-style aquarium. 

The most popular and intriguing factor of the ghost knife fish is its slender, blade-like body shape. These fish are a solid jet black in colour with a white stripe across their head and 2 rings near the tail. They also have no dorsal fin and just have a single extensive ventral fin that flutters and controls how the fish move. One of the coolest aspects of these fish is how they can swim backward perfectly which is a skill that is almost exclusive to knife fish. As these fish come from the wild, it may be advisable to put them through a quarantine procedure, this ensures that the fish are totally pest free and allows for the fish to adapt to captivity in a much more controlled environment. Setting up a small 70-liter tank with a cycled sponge filter, pleco caves, or PVC pipes as a form of cover and dim lighting will be a great quarantine environment. The first 48 hours is great to just monitor the fish to make sure there are no external problems like ich which can be developed through stress. From there a course of dewormer would be great to ensure there are no internal parasites. The fish should remain in here for at least 3-4 weeks before moving to the main display.

Trying to find the males and females in this species is very difficult as there are no immediate distinguishing factors between males and females. Captive-bred fish are generally bred in large ponds however these specific fish have come directly from the meta river of South America.  

Tank Recommendations for your Wild Black Ghost Knife Fish

Because the ghost knife fish can reach lengths upwards of 30 cm, they do require a fairly sizeable aquarium. An aquarium with a volume of at least 450 liters with an ideal aquarium size being 120 cm x 60 cm x 60 cm to ensure they have the swimming space required. The wild-caught fish will tend to be much shyer compared to captive-bred fish. It is best to give them a lot of tunnel-like structures and driftwood they can hide in and amongst. They can be kept on a sand or gravel substrate with no issues and will also appreciate plants in the aquarium as well.

Suitable Tank Buddies

Ghost Knife is big fish however they are quite shy and can be kept with a range of fish. They do not have aggressive personalities but the size of their tank mates does come into play when keeping ghost knives. However overly aggressive tank mates may also outcompete them for food especially when smaller.

Usually Compatible

Brown ghost knife fish, elephant nose, Discus, Giant Danios, and other peaceful but larger growing fish.

Sometime Compatible

Geophagus, Oscar, Convict cichlids, and medium-sized cichlids.

Rarely Compatible

Nano fish such as neon tetras or shrimp will become an immediate meal for the ghost knife when it is adult size.

Feeding your Wild Black Ghost Knife Fish

Wild black ghost knife fish may not take to any prepared foods for the first few weeks of being introduced to their aquarium. It would be best to start them on a diet of live worms that includes, earthworms, black worms, or white worms. They can also be fed frozen foods like Mysis shrimp or brine shrimp and once the knife fish is taken to this readily, an attempt can be made for pellets. It is best to feed them at night or to dim the aquarium lights prior to feeding.