After my wife noticed that I stared at these wonderful fish every time I went to the pet store, she reluctantly purchased me a pair. They are the most graceful fish I have ever seen, but their peacefulness can be deceiving. The morning after we put them in, it was discovered that they had gorged themselves on a school of baby neon tetras, which the person at the aquarium store had told us would not happen. Still, it's hard to dislike a fish that has such an innocent expression, and I wanted to switch to a larger fish anyway!
Well I am very sad. I lost my beautiful Ghost Knife last week. I had him for approximately 9 months. He had grown from 4 cm long when first purchased, to 25c m long x 4.5 cm wide. He gave me many hours of enchantment. My Ghost Knife came out at all hours of the day. Was trained to hand feed. Great feeling. Loved blood worm and brine shrimp. He got along great with the rest of the tank. I came home from work to find the Ghost Knife dead in the tank. Am going to invest in another ghost knife. But am waiting to upsize fish tank to 2 meters.
I was recently given a black ghost knifefish, about 30 cm long. This fish was raised for its first year in a 110 L tank. I must also mention that the owner was completly new to any kind of fish tank. For this first year the knife survived on shrimp pellets only. Also, I don't believe there were any water changes ever made to this tank. Unfortunately the fish was neglected, but lived to a healty 30 cm. Since the fish was given to me, I've placed him in a 200 L tank. There's lots of places to hide. My knife appears very happy, and healthy. I feed him shrimp pellets, dried tubifex worms, cichlid pellets, flake food, and some small sinking pellets. The knife is not shy at all, coming out often to feed or play, in spite of my extremely bright lights. The knife often swims straight up and down at the top while I feed him, hungrily devouring most anything I give him. Mine is often hugging the heater. It lived in a horrible environment for a year, and is beautiful and healthy in spite of that. I've had many freshwater fish, even some brackish water puffers. I do think the black ghost knife is the neatest fish to watch out of all the fish I've had. I've spent many of hours watching my knife. I also have an oscar (about 8 cm) and roughly 12 zebra danios. The zebras are just fancy food, since I don't want the risk of diseases that come with feeders. I am worried about the oscar and the knife getting along together, but so far they don't seem to mind each other. I don't think anyone should be afraid to get a knife fish. Make sure your tank is large enough, and has a good filter system. A little testing with the lighting and you'll figure out what your knife likes. Make sure the knife has a good place to hide. Vary its diet and you should be all right. Also don't forget the temperature. They like it around 25°C. Start with a small one, since they are a lot cheaper, and study up on the knife. I think they can make an excellent fish for anyone who can afford the tank to keep it in.
I have a Black Ghost Knifefish that is at least 30 cm long. I purchased him 4 years ago, when it was only 8 cm long. He lives in a 160 liter tank with several other fish. Anyway, he has always been docile during the day, but comes out periodically to check out the rest of the tank. Contrary to other experiences, my Black Ghost spends a large amount of time exploring the tank with the lights on and seems quite content doing it. He never feeds in the dark. Sometimes I will turn it out for him but he doesn't seem to care either way. He eats a hearty portion of brine shrimp once a day and has thrived under these conditions. I have tried many other feeding options, but he will only eat the brine shrimp. My clown knifefish spends every waking moment exploring and never hides or seeks seclusion. Both go against "normal" knifefish behavior patterns, but I beleive if you start them young in an environment like this they get accustomed to the routine and adapt accordingly. They are great additions to any aquarium whether aggressive, semi-, or community...don't be afraid to try them!
I had a black ghost for four years before being killed by the Brisbane council tap water. The memories I have are wonderful, especially the time the fish would sit in my hand thinking it was a cave. I found it was friendly with my community tank, including clown loaches, purple spotted gudgeon, rainbows and archer, but be warned: they knock off small fish and do not like the elephant nose because of electric pulses. They need a cave like a security blanket and mine only ate live food. It will come out during the afternoon if you do not feed at night. I will always remember what a character the black ghost truly is.
While most of the literature describes Black Ghost Knife Fish as being shy and nocturnal, they are highly adaptable fish which will make the best of their environment. If you want to enjoy watching these fascinating fish swim, try covering the top of the tank with floating vegetation, the diffused light will encourage them to come out and play. You can also habituate them to feeding when the light is turned on. A dimmer switch or a red lamp can also encourage light shy fish to come out of hiding. Another interesting habitat trick is to stack slate or other opaque flat objects against the front of the glass on an angle, firmly anchored into the substrate. This will create a cave which the Knife perceives as hidden from the other fish, but because you can see through the glass, he will be fooled into thinking he is alone and unobserved. Glass cylinders, such as oil lamp chimneys work well for larger fish. A clear drinking tumbler is also useful for smaller and more nimble fish. They do prefer caves with two exits.