The South-American Knifefishes thread

[amiidae]

Btw: Ben (Amiidae) must be our top expert given the enormous amount of species he has kept over the years. I hope he doesn't mind the following:

Top expert ? LOL ...I am far from it Marc.

[nvcichlids]

Ben, what was your experience with the centipede knives (Steatogenys duidae)? I have several feeding options, but was curious if they ever got to taking high end pellets or something like repashy? I have read a few threads about how they can be weaned onto high end pellets, but I will continue to doe blackworms and chopped earnworms, brine shrimp (fresh and freezedried) and anything else I think that might interest them.

[amiidae]

Unfortunately most of the knifefishes are pretty hard to get them off fm live or worms.

Usually those with large-size mouth species take cut shrimp and with luck... sinking pellets.

Personally I find the easiest to care are the Gymnotus sp but they are very aggressive.

[naturalart]

And - to my regret - copies of this publication are scarce and (thus?) expensive. There was one for sale on Ebay recently for 150 USD

As Marc said, it is pretty hard to come by. Found my copy in a small bookstore in Caracas.

Well, guess it could probably be awhile before I get one, Thanks for the info.

[Marc van Arc]

Sorry, not Ebay, but Amazon. Still available....http://www.amazon.com/Electric-Fishes-C ... cr_pr_pb_t

[bekateen]

If you want a little more of the taxonomy and diversity literature (no photos but a few diagrams of snout shapes; also includes habitat descriptions), there is this 50 page-long chapter from a book:

James S. Albert & William G. R. Crampton. 2005. Diversity and Phylogeny of Neotropical Electric Fishes (Gymnotiformes). In, Springer Handbook of Auditory Research Volume 21, pp 360-409. http://link.springer.com/chapter/10.100 ... 28275-0_13

The above link takes you to the published resource for this chapter, but it's not free. HOWEVER (not shouting, just emphasis), the pre-publication proof copy of the chapter is available for free at this website: http://www.ucs.louisiana.edu/~jxa4003/A ... proofs.pdf

James Albert's website (http://www.ucs.louisiana.edu/~jxa4003/Publications.html) has lots of other downloadable scientific publications on knifefishes also.

-Eric

[nvcichlids]

Well good news, 13 centipede knives will be in my tank either today or tomorrow night. Will post pictures once they are in..

excited~!!! trying to get more worm farms going to sustain a large population of worms

[Marc van Arc]

@ Nate: have your fishes already arrived? I hope they will give you a huge amount of pleasure. Please keep us posted.

Over here things don't look so bright. I currently keep 2 Elephant nose (Sternarchorhynchus oxyrhynchus) and 2 Mousetail knife fishes (Gymnorhamphichthys rondoni). People who have followed the story will say that of both species one specimen is missing, which is correct. Just vanished, never to be seen again......regretfully not uncommon in knifefishes.
Both Elephant noses (EN) were almost equally large when they entered my tank. Atm one has doubled in size, compared to the other specimen.
Both Mousetails (MT) were as long as the largest EN, but are far slimmer, more timid and entered the tank at a later moment. So there's no doubt which fish is in charge.
The MT's are not doing very well. They turn out to be picky feeders (they only eat live Tubifex worms and an occasional live red mosquito larvae afaics) and they are gently bullied by the large EN, especially during feeding time. I have bought a huge amount of Tubifex today to try to save the specimen that I could catch by hand yesterday - which is of course not a good thing, as I'm not that fast. So you can replace the photo caption "sloppy digger" on the previous page by "weakened digger". It's no longer able to bury itself properly.
Fingers crossed, but I have already figured out that the Mousetail is a fragile species, which should preferably be kept in a species tank or kept together with other timid, small fishes. Another knifefish species combined with an enthousiastic bunch of mid sized auchenipterids seem too much for them.

[Marc van Arc]

Damn, the quality of that Tubifex was so incredibly poor that I had to throw everything away.
I had previously bought good quality from this person and he can deliver large amounts (half a kilo in my case). The fact that I will get my money back is nice, but the fact that I can't feed the proper food means the almost certain death of one of the Mousetails.....
I'll try small frozen foods tonight, but my hopes aren't high. Maybe the poor thing is beyond recovery anyway.

[kruseman]

In 2011 I had the opportunity to keep 2 Adontosternarchus sp. :

[KungFish]

In 2011 I had the opportunity to keep 2 Adontosternarchus sp. :

What were their general care requirements? Feeding, temperament etc.

[nvcichlids]

My fish are all doing fine (from what I can tell.) They arrived Tuesday, and I have been extremely busy with work and household stuff.

They really scare me. Some days they will sleep on the bottom all day/night and not move for anything, then the next morning... POOF they are ALL swimming around. I don't know if this is normal or not, but I have seen them/read they sleep like that.. maybe mine love to sleep.

They are housed with a quad (1m/3f) pearl gourami's that I couldn't find a house for in time, and some sterbai corys. They all seem to be doing fine together. I will post pictures as soon as I have them

[kruseman]

What were their general care requirements? Feeding, temperament etc.

I kept them in water of about 26 degrees.
Water: soft and acidic. ( 2 KH pH 6 )

They ate black, white and red mosquitolarvea but, as far as I can remember, dry food wasn't accepted.

Dormant during the day in floating plants and active during the night.
Quite fragile animals and a species not to be combined with more active and "bossy" tankmates like cichlids.

[Marc van Arc]

The quality of that Tubifex was so incredibly poor that I had to throw everything away. The fact that I can't feed the proper food means the almost certain death of one of the Mousetails.....
I'll try small frozen foods tonight, but my hopes aren't high. Maybe the poor thing is beyond recovery anyway.

Tougher than I expected! Got better quality Tubifex last Saturday, fed a lot and both mousetails seem to improve. I'm currently also feeding live red mosquito larvae and they do take the smaller ones - their mouths are incredibly small. The burying ability is also improving. It strikes me though, that these fish search for food in the sand, rather than on the sand. If they happen to stumble into a bit of live food on the sand they will eat it, yet it seems this happens by accident rather than on purpose.

[Marc van Arc]

I currently keep 2 Elephant nose (Sternarchorhynchus oxyrhynchus) and 2 Mousetail knife fishes (Gymnorhamphichthys rondoni). People who have followed the story will say that of both species one specimen is missing, which is correct. Just vanished, never to be seen again......regretfully not uncommon in knifefishes.

Yesterday evening I saw all 3(!) Mousetails at the same time. Quite incredible. I had to look (and count) several times to believe it.

[Marc van Arc]

Yesterday evening I saw all 3(!) Mousetails at the same time. Quite incredible. I had to look (and count) several times to believe it.

And when I looked more closely, I noticed deep red gills and regular rubbing the gill area as if they had white spot. Gyrodactylus or Dactylogyrus aka gill worms. To cut a long story short: they have all died by now. Despite medication, I think they were "beyond repair", as they were unable to eat and thus unable to recover. This must have been going on for quite some time, which is of course fatal in the case of fishes you only get to see in the dark (blue light). The reason I noticed they were ill was because I started seeing them during the day and their lethargic behaviour left me with only one conclusion.

Nevertheless, I'd recommend this species for a species tank or a tank with small and non-competitive co-occupants. Small, bottom orientated live food should be available as well as a thick layer of fine grained sand, so the fish is able to bury itself.

[Marc van Arc]

My fish are all doing fine (from what I can tell.) They arrived Tuesday, and I have been extremely busy with work and household stuff.
They are housed with a quad (1m/3f) pearl gourami's that I couldn't find a house for in time, and some sterbai corys. They all seem to be doing fine together. I will post pictures as soon as I have them

Nate, are things still working out as you expected?

[nvcichlids]

Sorry, been super busy/lazy lol.. Yes. still have yet to add the hatchetfish as I had hoped, but all knives are active and seem to be doing fine. I haven't lost any. I still don't see them actually feed, but their activity increases when the worms hit the water. I believe I have two species (Steatogenys duidae and Steatogenys elegans).

it still scares me to see them resting/sleeping near/on the bottom.

feedings have consisted of chopped up trout worms (not sure of the sp), frozen black/blood along with live black worms and brine shrimp. They aren't fat as i had hoped (was hoping for more girth, but they are all still active and moving)

I also recently added a large amount of oak leaves to the tank, it has sub-dued the lighting and they are more active during the day, but still not considered ÄCTIVE fish.

[wrasse]

Hi Nate, it sounds to me like the race is on.

The race being to see their stomachs full and to actually observe them eating, before seeing them getting thinner!

IMV worms are definitely the right food to help them fill-out.

Can you post some pics please.

[wrasse]

Hi Nate, it sounds to me like the race is on.

The race being to see their stomachs full and to actually observe them eating, before seeing them getting thinner!

IMV worms are definitely the right food to help them fill-out.

Can you post some pics please.

[Marc van Arc]

Despite medication, I think they were "beyond repair"

Or otherwise the medication itself would have killed them.......
Beware, don't use any medication containing flubendazole on electric fishes!! Most brands available in The Netherlands (Lernex, Dacticyd, Gyrodol) have that information on their inserts (referred to as elephants noses and the likes), but CamaCell doesn't - and that's why I bought it, believing it was safe to use on my fishes.
Nevertheless, it does contain flubendazole, which is currently killing my poor large Elephant nose Knifefish (the smaller one has not been seen for days, so I expect it has already died). It hurts my eyes to see such an elegantly moving fish bumping into every obstacle, barely knowing whether it is going forward or backward and swimming in circles on its side, unable to swim straight up.
Also the Ageneiosidae are certainly not amused by this worm killer - which does even more than it promises.
This reminds me a lot (alas) of the current threads about the dying Hoplo's due to anti-worm medication.

[wrasse]

Beware, don't use any medication containing flubendazole on electric fishes!!

I have to say my experience is different Marc. For many years I have used Wormerplus which contains flubendazole, in a tank containing glass knife fish.

[nvcichlids]

Well they aren't getting fatter, but definitely not getting skinnier. I did see two of the bigger ones picking up chopped trout worms (my worm farm is doing well, so this is a plus as well.)

I will charge my camera's battery at lunch and hopefully get some pictures tonight.

[Marc van Arc]

Beware, don't use any medication containing flubendazole on electric fishes!!

I have to say my experience is different Marc. For many years I have used Wormerplus which contains flubendazole, in a tank containing glass knife fish.

Well, in that case I wish I had used your medication - despite its rather silly name (one would expect Wormerminus rather than Wormerplus). Maybe the flubendazole concentration in your product is less? Anyway, that brand is not available over here afaik.
My biggest concern is that all other brands I know of warn about not using the product with mormyrids and gymnotids, except CamaCell. That should be changed imo.

On a side note: the Elephantnose is still alive and much quieter atm. This afternoon I added a product called Sera Toxivec, which is able to get rid of all kind of nastiness (according to the bottle, that is). Let's hope this does any good. If not for the knife fish, then hopefully for the other fishes.

[wrasse]

Several years ago now... I spoke with the supplier of Wormerplus and he said it's a very safe product to use and hard to overdose. I've used it regularly since then with all my fish.

However, with newly acquired knife fish (and most other fish), I would treat with a tonic and salt mix. This is to help get them adjusted and feeding, whilst suppressing infection of any kind.

[nvcichlids]

pictures were taken, internet was down all night.

[nvcichlids]

Something is wrong with my internet at home. i will be working on it tonight. I did find a single casualty. This was the runt of the group. I am guessing he hadn't been eating with the others (as he was really thin). I also know he was one where I could see his tail in the cave under driftwood they swim through,hide in, but never really out. I saw (what I believe is everyone else) out eating last night. Frozen (not live) blackworms were the key. They also seem to like the added leaflitter bottom.. I don't know if it stimulates natural feeding behavior in them or what?

[apistomaster]

Hi Nate,
I think we have a great deal more to learn about maintaining the various rarely seen species of SA Knifefishes. I think having ample leaf litter is a good idea. It ought to provide much surface area for them to forage off and supplies easy hiding places.
Aside from our lack of knowledge about most SA Knifefishes' biology and ecology we usually receive imported wild specimens which have been stressed and starved for up to several weeks before they ever reach our tanks. SA Knifefish are probably more sensitive to the bare and stressful conditions typically found at any exporter/importers' holding tanks than most other more commonly available species. So many arrive already at death's door that any survive at all for any length of time is an accomplishment. For many decades wild Discus also were often ruined by the time they reached their final destinations. It took decades before all those involved with their capture and sales mastered maintaining them properly. Most now treat theirs with antiparasitic medications and acclimate them to moderately hard water with about a neutral pH prior to selling their wild discus.
The vitality of wild discus sold now is much better and customer success rates have improved.
SA Knifefishes need similarly specialized care and acclimation but they are and most likely will remain novelties. Hopefully there are now at least a few dealers who specialize in offering the rare and unusual fishes like these are already doing their utmost to ensure their fish are sturdy before allowing the sale.

[Marc van Arc]

Yesterday I helped the elephantnose out of its misery.
Due to unwanted and unexpected side-effects of Camacell as well as my own apparent incompetence, all knifefishes in my tank have died.
More victims shortly in the Auchenipteridae thread. Yes, this is cynical, but it's reality - alas.

I hope all people involved in this thread will keep on enjoying their knifefishes. They are worth it!

[wrasse]

I totally agree with Apistomaster's views here... and it explains why we don't see many communal knifefish species available to the hobbyist.
It's as if, by the time these fish reach the retailers' tanks, their digestive system has all but shut down. And it's not until they reach the home aquarium that they get specialist attention. There's also parasites and other infections to complicate matters further.
Ghost knives and carapo types are less complicated, but I've yet to see a Gymnotus Pedanopterus available in the shops (which I would like).
If I come across Steatogenys species, particularly S Elegans... I'll try them, but I've not seen any for a long time. And small trumpet-nosed knives too.
Marc, we share the same taste in fish keep a look out for Trachydoras Steindachneri, they're grrrreat! And for a real challenge - Lamontichthys species! Don't lose heart.