Black Ghost Knifefish

[amy1994]

What sort of fish can they go with? I have 2, and they are kept with some plecos, loaches + discus. I keep the discus in reconditioned tap water, but i've been told they have different requirements to BGK, i just don't know what they are. They are kept in a 120cm x 45cm x 75cm tank, and they have various places to hide, and i'm also planning on putting more in there so that they all have their own space. I would like a shoaling fish, before i had the BGK i was thinking of having cardinals, but i don't want the risk of them being eaten. What shoaling fish is big enough not to be eaten?

 

[simonas]

Hi Amy

Cardinals would certainly be eaten. BGKs are predators that get to a large size in the aquarium certainly .One willl be too big for your tank never mind two or more#

They are lovely fish as are discus and although I once kept a BGK with discus yrs ago I wouldsay you need to concentrate on the discus and get a big shoal of cardinals whilst getting shut of the BGK's or get a bigger tank for the BGKS

Theres ots of info on BGKs on this site as they are great fish and popular as a result but your tank at this stageisn;t suitable for them IMO

 

[Davo86]

i've been told they have different requirements to BGK, i just don't know what they are.

BGKs come from cooler, oxygen rich fast flowing waters whereas Discus are from warmer still waters that will ultimatley have much lower o2 levels, making them really unsuitable tankmates, Also I realise I have said it before but keeping two BGKs will really only ever end in trouble

What shoaling fish is big enough not to be eaten?

Anything full bodies that is over 2-3" should be fine, however with Discus in the tank, other Medium/larger fish wouldn't make the best of tankmates for them IMO.

 

[amy1994]

Okay thanks

 

[zeke the black ghost knife]

ooh i have knife fish too! lol
introducing zeke, the most famous bgk on trpoical fish forums!

 

[TwoTankAmin]

BGKs come from cooler, oxygen rich fast flowing waters whereas Discus are from warmer still waters that will ultimatley have much lower o2 levels, making them really unsuitable tankmates

Both Mongabay and Badman's disagree with this. These two well respected sites both suggest discus as suitable tankmates. They also both list the upper temp range for Apteronotus albifrons as 82F which is a fine temp for wild discus.
Mongabay and Badmans

Moreover, Heiko Bleher does not agree with this statement. In fact he will tell you they go together in a biotope tank. The following comes from his site:

Hello Heiko
You have helped me finally decide what sort of biotope I would like in my tank; although I will not be using the wild discus that you used, nor the ray. I would like to do something similar to your CABURI – LOWER AMAZONIA, BRAZIL and wondered if you could supply me with a bit more information.
What were the dimensions of the tank that you used for the biotope? What type of stand was used to support it?
What type of rock is used on the right hand side and what would you estimate the weight to be?
Would it be possible to use artificial rocks instead and if so then do you have any recommendations? As I have weirs in the back corners of my tank I would like to have a formation coming at a diagonal which would mean much more rock and I'm slightly concerned about loading one side of the tank.
Would the Geophagus and Satanoperca be ok with fine gravel or do you recommend solely sand? If sand then what would be the maximum particle size?
I have noticed that some people keep Apteronotus albifrons (black ghost knife fish) with their discus; would they be correct for this biotope or are they from a different area?
Thanks
Gibby, Yorkshire - UK, 30 November 2010

Answer from Heiko Bleher:
Hi,
sorry for the late answer, but I was not informed and I am extreme busy for PFK and for volume 2 to finalize everything.
Here some answers to your questions:
Q.: What were the dimensions of the tank that you used for the biotope? What type of stand was used to support it?
A.: 200 cm x 60 cm x 60 cm, just wooden pallets
Q.: What type of rock is used on the right hand side and what would you estimate the weight to be?
A.: Red Lava stone, easy to get and no heavy - same as on the cover of my book: Bleher's Discus volume 1 (and the description inside).
Q.: Would it be possible to use artificial rocks instead and if so then do you have any recommendations? As I have weirs in the back corners of my tank I would like to have a formation coming at a diagonal which would mean much more rock and I'm slightly concerned about loading one side of the tank.
A.: Lava stones do weigh nothing, very light rocks.
Q.: Would the Geophagus and Satanoperca be ok with fine gravel or do you recommend solely sand? If sand then what would be the maximum particle size?
A.: You should have some gravel and some sand - definitely both.
Q.: I have noticed that some people keep Apteronotus albifrons (black ghost knife fish) with their discus; would they be correct for this biotope or are they from a different area?
A.: Yes you can keep them, but not small ones.
Best regards
Heiko Bleher
www.aquapress-Bleher.com

From Aquapress Bleher

 

[amy1994]

Thanks everyone

+ heres a pic with them together... sorry for the bad picture quality