Black ghost knife


Hey guys, justa querie about the Black Ghost Knife fish, I saw one in the lfs and I just HAVE to have one ;D. But before I go race ahead and grab it out of the fish tank I need to know a bit about them....
Here goes,
1. They were pretty small at the lfs about 1and a half inches but were they just babies or are they that big
2. Are they aggressive fish? Will they eat my small neons? Will mthey get along in a community tank?
3. What sort of food do they eat, I didnt see a profile on them in fishlore
4. What species are they ive never even seen them before!!

Thanks in advance


sometimes black ghost knife fish can be aggressive to its own kind but they are normally peaceful, u can keep angelfish, gouramI and discus with them. they are shy and sensitive to bright lights, u can put some floating plants and driftwood. I don't know how big they can grow. feed them live shrimp and meaty frozen food. I think they are schooling fish.


Ghost knife fish are able to grow from 16 to 20 inches long. They need a really big aquarium. They will need some spaces to hide behind now and then to feel happy and safe. Ghost Knives are not THAT aggressive but I should emphasize that all omnivorous or carnivorous fish will sometimes go after fish that look small enough to eat and swallow them. Neon tetras are for instance a nice snack for them.


From what little experience I have with Ghostknives, I can tell you three things..(1) They're expensive!!..(2) They're high-maintenance, requiring a perfect diet, a large tank, the right tankmates(surface feeders), and somewhere to hide since they're not comfortable with bright light.. and(3) They don't do well in tanks with gravel, since they're bottom-feeders for the most part, and have extremely sensitive skin, which can bruise if they're feeding in gravel.

Bottom line, they're incredibly beautiful fish, but require so much maintenance, that they're recommended for fish-keepers with a great deal of experience and money to invest in the perfect tank setup for them.

I should however mention, none of what I've said is written in stone, and if I've learned anything in the time I've gotten into keeping fish, it's that many of the rules in this hobby have their exception, so please take what I've posted only as some kind of guide.


  I currently have a Black Ghost Knife fish and have had now for about 8 months.  It is 7 or 8" and is one of my favorite fish!   Before buying I asked my local fish expert about it and this is what she said:
* If raised from a small  say 3-4" size with small fish they generally will NOT see them as food, and even though their jaw WILL open very wide, if they are raised eating food from you, they will not eat small fish.  She had one 18" long that she hand fed, it was that friendly and trusting and never ate her other fish no matter how small.   My fish is currently in a community tank with 9 cardinal tetras and I haven't lost one!

*Like stated before they are shy of light, however if they are hungry, and you are feeding they will come out to eat.  They will race up to the surface grab the blood worm cube and scoot backwards down to their hideout.  They go backwards just as easily frontwards.

*They commonly lay totally still for hours on end, and you will think there is something wrong, but that is just their nature.

*They have sensory perception of food going by, they do not have good eye sight.

*Having a skin, instead of scales they can be burned by medication, and just like other sensitive fish, care must be used not to use more than 1/2 strength if you have other fish that require it. (Best to use a hospital tank anyway).

*I have not noticed they are particularly sensitive to ph, mine is 7.2 -7.4 which has been fine, my temp varies between 74F and 80F depending on my generator power being off at night, and the heaters running during the day. My ammonia is always 0 - .25, Nitrites 0 and Nitrates usually 10 - 20.  I change 50% water every other day, as my tank is overcrowded, which he puts up with very well, even sharing a "lair" with a catfish AND Royal pleco that also like to hang out with him..... The BGK sits with his head next to the cat, the Royal p. stuck to the top of the hide out, they all think I can't see them but.....ha ha ha 

*My experience is they are not picky eaters.  They eat bloodworms, shrimp pellets, and do most of their feeding at night.  I have several fish that do this, so usually my last feeding of the day are the bloodworms, brine shrimp and shrimp pellets and algae wafers, so of all that he seems to be quite satisfied.

*Adequate cover needs to be provided, so they have plenty of hiding spots, but they feel just as hidden in a bunch of Java fern as they do in a cave.  As a matter of fact they will sit, upside down swaying back and forth thinking they are totally hidden in all that green, but of course you can see them very well, its so cool.  8)   So if you want to see more of them, plants, driftwood, and rocks situated in such a way that they can "hide" but are actually up next to the tank side will insure your enjoyment.

*Lastly since they do grow quite large and are so loveable, I wouldn't commit myself to one unless you have a fairly big tank, my 55 gal is too small, and only if you also commit yourself to getting a much larger one as they grow.   

*My fish lady said she had hers quite a number of years!

My recommendation.   If you can commit yourself to this fish for years to come (because you will love it), and can give it lots of room in a large tank.  You will be glad you added it to your community tank.  Best of luck

Fish in the Frozen North.    -6 F this morning.    


They are great fish however,  and My experience is they are not difficult.

Fish in the Frozen North!

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