Black Ghost Knifefish

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briandoran

Aquarium Advice Apprentice
Joined
Feb 18, 2006
Messages
18
Location
Dublin, Ireland
Hi folks,

I'm new to fishkeeping.

My tank set up is: (new and only a few fish so far)

120 litres (not sure in gallons)
2 Sailfin Mollies (1 male, 1 female)
4 Guppies
3 Blue Coral Platies

and over the weekend I bought a Black Ghost Knifefish. I didn't know (wasn't informed) that it would grow so big! Can grow to 18"!!

So my main question is? Are my other fish at risk from this BGK or will they be alright? Also, is my tank too small for this guy?

Thanks for any info ...

Brian
 
i had a BGK in my 30 gallon it was fine it is blind so it needs a good place to hide where it can feel around its body. i had a plastic pvc tube . and depending on the size tank your fish will grow toits surroundings. no worries
 
I had a BGK in my 30 gallon it was fine it is blind so it needs a good place to hide where it can feel around its body. i had a plastic pvc tube . and depending on the size tank your fish will grow toits surroundings. no worries

This is not true...It might "grow" to its surroundings in a very mutated way. A smaller tank might cause the fish to become deformed if it doesn't have the space it needs to be full grown. A black goust knife fish in aquarium don't normally get larger than 18" however in wild can grow as big as 24" a black goust can live in a 4ft by 1ft aquarium until it reaches 1ft in length then it is best to move it to a much larger aquarium so it has room to strech across the width of the tank at least. So the aquarium should be at least 4ft by 1'6".

If you can't accomidate the fish's needs my suggestion would be to see if you can find an aquarium society or club and give it away once it has out grown your aquarium, or see if you can return it back from the fish store.

As for a pvc pipe...a 3" wide pipe that is 12" long will work for a long time.
 
how big is the bgk now? it is my understanding that they are agressive, and will eat anything that fits in their mouths. i would say that eventually your other fish will be lunch.

and i second what japola said--fish do NOT stop growing just because their tank is too small. a small tank may curtail their growth, but it will also curtail their lifespan and quality of life. if your tank can't handle the adult size of the fish, you should consider upgrading to one that will, or give the fish away to someone who can house it properly.

that being said, if the bgk is small, you can keep it in a smaller tank until it starts to get too big. then you have to move it.

bgks are beautiful fish! have fun with it, and treat it well :)
 
no, guys. a black ghost knife will get to be roughly 8-12 inches in an aquarium. just give it lots of room, like a 3" long to accomodate them. no need to egt extra wide tanks and such.
 
heres some specific information on the knife you have right now:

"Black Ghost, Sternarchus Albifrons, is found throughout the waters of the Amazon River. They are very peaceful and friendly with all but the smallest of aquarium mates and are even known for taking food directly from the hand of their owner. This species is not a fussy eater and is happy with dry, frozen or live foods. The coloration, though not as impressive as its size, is very distinct to this fish. They are jet black with a white stripe on their back that stretches from the head to the dorsal fin. They also have two white bands on their tail towards the end of their bodies.
"Though these fish rarely exceed 6 to 8 inches in the home aquarium, they can grow up to 18 inches in length in the wild. They are happiest in soft, slightly acidic water though variations in water conditions are easily taken in stride. The dark and mysterious Black Ghost makes a welcome addition to any aquarium and is a good fish for all experience levels." -www.petsolutions.com
 
I had one in an 85 gal tank when I was a kid and when we had to give it up because of movieng it was at least 15"(inches) long. And i have since then seen 3 more that were all atleast a foot or better. The ones my lfs has are 5 inches long at sale. I think pet solution relizes not every one has a large tankand are trying to sell fish. Just my 2 cents.
 
I have seen SEVERAL BGK's that are at least a foot long. Fish should not be kept in aquariums that cannot accomidate their full size. I am willing to bet that the 6-8 in sized ones died at an early age. That would explain why they were so small. I would say that if you actually CARE for your fish, you will get rid of him or consider a MUCH larger tank. I wouldnt even put one in my 55g. In fact, I have personally given fish away because they were going to grow too large for my tank. If you keep that fish, you will be doing it a great injustice IMO.
 
Check out badmans tropical fish look under profiles. they say that the black ghost grows to 40" in the wild. I would personly not put this fish in anything under a 75 gal.
 
Oh they are amazing very personable fish the one we had you could reach in the tank and he would come rite out and swim into your hand. We used to hand feed him tubiflex worms his name was Curly we had him atleast 6 years.
 
Mghslowell said:
i had a BGK in my 30 gallon it was fine it is blind so it needs a good place to hide where it can feel around its body. i had a plastic pvc tube . and depending on the size tank your fish will grow toits surroundings. no worries
You say "had a BGK in my 30 gallon". Why had? What happened?
 
I finally set my eyes on a large BGK at the LFS yesterday. He was a good foot long, about the length and thickness of an english cucumber. It was amazing! I have never seen one over a few inches before this, so it was quite a cool thing to see.
My son has one in his 30 gallon tanks, but it is just him and a pleco. When he gets bigger he will go into the 65 gallon community tank. I just think they are beautiful fish, graceful and elegant looking.
 
Thanks to everyone for their replies .. much appreciated.

He seems to be hiding under the plants all the time .... this is normal I know but was wondering whether the light actually damages them? I know you can get a ghost tube (clear tube for viewing) and this tricks him into thinking he is hiding.

I don't want to do this if it would be bad for him to be exposed to light unnecessarily.

Any ideas.
 
hEY Briandora,

An idea for viewing and keeping the Ghost away from the light ( and sorry, but I dont know if the light hurts it or not ), and view it at the same time. Get a piece of PVC pipe that its diameter would acomodate the ghost tube...either slide inside the pvc, or the pvc slided in the ghost tube. Cut a couple of rectangle shaped windows all along one side of the pvc pipe.
Something like this [__=======__]. Leave some 1/4 in between windows...and youll be able to see the fish and keep him away from the light above ah! What an Idea no???

Well was just a thought... if you are good with your hands..you'll have fun!
Hope it helps. And lots of fun.
 
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