My experiences with Adontosternarchus nebulosus, also known as the clouded ghost knifefish.

[fishhead0103666]

Hello, I would like to share my experiences with Adontosternarchus nebulosus which are also known as the clouded ghost knifefish. These are a relatively new species which were only discovered in 2007 and just in 2019 I started seeing them pop up for sale a mere 3 times or so. I bought one each time but two times they died within 24 hours and the other time it was dead on arrival. I have found them for sale recently and purchased two however I will get into that a bit later. Here is an article from the latest Amazonas magazine.



Now I shall go onto the fish themselves.I originally had the two knives separated as I was concerned that the two would have issues and they both prospered while separated. I ended up moving them together and immediately I saw a bit of aggression as the one that was in the tank beforehand went and nipped at the one that was introduced into the tank a few times. It led into chasing, all of which ended within a minute or so but it set the stage of their relationship as I see now. As time went on I noticed the original one eating while the added one held back, I believe that the original one had become the dominant one and prevented the other one from eating. There was no physical aggression besides from that first minute but the hierarchy was still there which led to the death of the added one I believe. I was looking for him a while before writing this thread to take pictures and I found him dead in the fake plant he always hid in which led me to believe that he starved to death as he started eating less after being introduced to the other one compared to when he was kept by himself. Due to the article above I believe that they are peaceful, develop a hierarchy, and while peaceful they are aggressive in slight ways which I find similar to brown african knives. I believe it was Hendre who when he lost a knife or two the rest of his group turned on the remaining ones as the hierarchy had been disrupted.

Now, I had been planning on getting 6 more for a group of 8 but given that I just lost one, the one that looked better at that, I suppose I’ll get 7 more to test out my hierarchy idea.

From what I’ve witnessed they aren’t picky with their food as I fed them a mixture of omega one flake food, tetra flame food, new life spectrum floating regular pellets, new life spectrum algae max pellets, along with freeze dried blood worms.
Now for habits I’ve noticed, they seem to like hiding in plants, I’ve given them both fake plants and real plants and it would appear as though one used one while the other used the other. The original one used the real plant when I put it in while the added one stayed to the fake plant, they would occasionally change but for the most part the two stayed to their own plants. Looking back on this I wonder if it was a hierarchy thing but I’ll have to wait to find out. The added one that ended up perishing, close to the end of his life, he would go up to the top of the tank at night and somewhat hover on his side while swimming every so often short distances. I chalked it up to an odd quirk or just something the species does such as upside down catfish swimming upside down but it didn’t occur to me that the other one didn’t do it as well, looking back on it now I believe it was a sign of him being close to death perhaps. If the remaining one or any additional ones I should procure do it then I shall let it be known here. Regrettably I haven’t been able to observe them too much at night so I can’t say how they act at night so I will update y’all on that in the future.

Now I will provide some pictures of the remaining ones since I hadn’t taken any pictures before tonight. They are all rather poor as the knife was moving nonstop and even with photo bursts I only got 2 which were very similar shots.




Now for a personal comment, when I first saw this fish, which was labeled under the name of “granite marbled knifefish” (you’ll take notice in the picture of the article they were sent labeled as “marbled knives”) and the first picture I saw of them I was in love with their coloration, a mixture of black and white, what’s not to love? I did some quick research but found next to no research and I realized something, this fish which I’ve come across is next to unknown in the hobby, I had a chance to go out on a limb and help a lovely new species of fish get more well known in the hobby. I took that idea and ran with it. I found them for sale 3 or 4 different times and at a cost of $50 per fish and then shipping for each time I did not hesitate to keep getting one after the other even though each one died as I was and am determined to bring light to this species, it is my honor to do so. I wish to learn how to breed them so that others may do so as well thus giving this wonderful species a chance to be more well known, dare I say, common in the hobby. A way to shove my love and appreciating towards the species if you will.
Here is a thread I started earlier which had some talk about the knifefish

Guess what’s in the box

I’m getting 2 different species on Tuesday from aqua imports, guess what they are. Hendre, once again you are not allowed to guess as I’ve talked about this before to you.

www.monsterfishkeepers.com

Turns out I did take one picture before tonight which is of the surviving knife.

 

[Ogertron3000]

This is going to be an interesting thread, it looks like an investment for you already. Hopefully you will have better luck with the next few deliveries.
What is it about them that keeps you coming back for more? Do you like the novelty of a relatively new species or you want to crack their mysteries?
I doubt we will ever get them here but they look like a very interesting species to keep.

 

[Hendre]

Nice writeup, sorry to hear about all the losses.

Did you keep track of the water parameters and such? I am surprised there was not much info in the amazonas magazine, but I would think a softer water system would be ideal. Addition of tannins could also be useful, be it through use of leaves or other botanicals. Boiled Rooibos (South African Redbush) tea is a good source of tannin as well.

Do you have any photos of your prior setup? And do you have any modifications you think you would make to the tanks?

 

[fishhead0103666]

What is it about them that keeps you coming back for more?

I’ve always wanted someone to ask this question but didn’t expect it until a decade or so down the road when I had hopefully made some noticeable progress on my projects.

I’ve found a few fish that either right when I saw them or soon after I knew that I truly loved them and whenever I love a species I want to show my love and appreciation towards it and the only way I can think of is getting the species more well known in the hobby, it helps that every species I’ve felt this way about have all been uncommon. So far the species I can remember off the top of my head are Wallace’s shoehead catfish, this knifefish, and short tail nurse sharks. Each of these fish captivated me in some way immediately.
The catfish just has a certain way about it that shows how graceful and majestic they are while not needing to be colorful or flashy.
These knifefish have a nice simple body shape that looks right and when combined with the contrast of black and white just looks right to me. It’s not a severe contrast like a zebra pleco where it’s a bright white which comes to a screeching halt to a deep dark black, it’s just a beautiful blend with the occasional patch of bright white. The one that died had the bright white and dark black patches sadly, the one that’s left doesn’t have those occasional bright whites or dark blacks. The fact that the members of this species don’t all look the same, like neon tetras, is nice which adds a bit of fun. The ones that died before the latest loss and the current survivor all looked similar but with noticeable differences, the one that just died looked vastly different, it looked a lot like the one in the article.
As for short tail nurse sharks, the fact that there are various sharks that all get too big for the vast majority of aquarists to handle that people can get with relative ease greatly annoys me. Tell me, if you have lets say $2k-$3k then what sharks can you get? Off the top of my head I can think of horn sharks, port Jackson sharks, cat sharks, black tip reef sharks, maybe a fine tooth shark, you could surely get a nurse shark. You can get a good size tank for $2k-$3k, somewhere around a 300 brand new I think, bigger if used. Now think about those sharks, I could only think of a few sharks that get big you can get for the $2k-$3k, there are probably more. Now how many people will have that 300 gallon? Maybe 1%? Now how many people will have a tank big enough to house the bigger sharks I listed? Maybe 1%-10% of the 1%? I want to make it so that there is a much higher chance of someone being able to get their “shark week fix” with a smaller shark that fills the niche just as well as other sharks.

Nice writeup, sorry to hear about all the losses.

It’s part of the hobby, this hobby is not for the faint of heart nor the light of wallets as I like to say.

Did you keep track of the water parameters and such?

I have been however my papers that I had been using to write them down on got knocked into a bucket of dirty water recently and got ruined so I’m having to start over.

I am surprised there was not much info in the amazonas magazine,

As am I.

I would think a softer water system would be ideal.

That might be ideal but it is not feasible for me as my ph is naturally at 7.6 or so and I’m not ready to start messing with ph to do some tests. In the future it’s something I’ll be looking into but not yet I’m afraid.

Addition of tannins could also be useful, be it through use of leaves or other botanicals.

I hadn’t really thought of that but I do have some of those tannin leaves that shrimp keepers use often, almond cappa I think, that I can use.

Boiled Rooibos (South African Redbush) tea is a good source of tannin as well.

Interesting, thank you for this suggestion comrade, I shall look into this certainly.

Do you have any photos of your prior setup?

The set up hasn’t changed in any noteworthy events since it had the same amount of fake plants when I put them in as it does now. The only difference is I added a big amazon sword and a medium one. I’ll take some photos tomorrow as it grows late into the night as I type this.

do you have any modifications you think you would make to the tanks

To be honest I’m not quite sure what possible tests I could run on the tank decoration wise as I can’t seem to think of anything that would make a noticeable difference. Driftwood doesn’t seem like it would make a difference. Floating plants don’t seem like they would make a difference. This species seems to like plants for hiding but I am going to be trying pvc pipes and fake driftwood caves so I’ll report on that. I’m thinking about trying to find out if they prefer floating food or sinking food in order to feed more effectively.


All in all, there’s a lot of tests to run and research to do and whatnot before I have anything that’s moderately useful for keeping the species so this thread will likely stay quiet with random tests and whatnot being reported upon until I stumble upon something important relating to the husbandry of this fine species.

 

[Hendre]

That might be ideal but it is not feasible for me as my ph is naturally at 7.6 or so and I’m not ready to start messing with ph to do some tests. In the future it’s something I’ll be looking into but not yet I’m afraid.

What's the kH/gH? Since that is a bit more important than the overall pH sometimes.

I hadn’t really thought of that but I do have some of those tannin leaves that shrimp keepers use often, almond cappa I think, that I can use.

Those break down nicely into detritus and biofilm that shrimp love but I can't say I have seen a lot of tannins. Using tea or other tannin-rich botanicals gets more bang for your buck.

The set up hasn’t changed in any noteworthy events since it had the same amount of fake plants when I put them in as it does now. The only difference is I added a big amazon sword and a medium one. I’ll take some photos tomorrow as it grows late into the night as I type this.

I would try and make it as natural as possible, my tank was barebottom for a while and the knives did not like it. Some substrate and substantial cover would go a long way imo. With decent planting and varied hiding spots my knives were a bit busier, which may also apply to these.

Also what size is this tank you plan on using for the group?

 

[fishhead0103666]

Making it natural is the goal as if I can recreate the environment they come from then they’re more likely to breed.

As it stands once everyone is quarantined and eating well I plan to put them in a 55 and see how they are from there. I feel as though a 55 would be appropriate for a group of 8 but I won’t know for sure until I have them.

 

[fishhead0103666]

I forgot to say that I will test the gh and kh later today and will be looking into getting some of those botanicals and whatnot.

 

[blackbullhead]

Interesting write-up. It's awesome to see knifefish getting some attention from serious hobbyists. I want to point out though, that neither your fish, nor the one shown in the article are actually Adonto nebulosus. True nebulosus has a large pale region at the base of the tail (see photo). The fish in the article is A. balaenops and yours is A. clarkae. In terms of aquarium care, I don't think there would be any practical differences (at least based on the little known about any of the species).

 

[fishhead0103666]

Interesting, according to what you say I have had 1 Adontosternarchus balaenops, and at least one Adontosternarchus clarkae and possibly 3-4 more clarkae. I’ll have to do some research about the distribution of these species, thank you for bringing this to my attention. It certainly is very interesting to know that the species isn’t similar to guppies as I had previously thought they were with a wide variations of patterns.

While I may not have obtained an actual Adontosternarchus nebulosus I now realize that the fish that I actually wished to do my thread upon is likely called Adontosternarchus balaenops.

Do forgive me for my wording as it makes it sound like I don’t believe you which is not my intention, I wish to research it for myself before I say things as fact.

I will likely end up having a mod change the title a bit further down the road to the correct scientific name of whichever species comes into my possession.

 

[blackbullhead]

No worries, the original description for A. nebulosus (Lundberg and Fernandes, 2007) is the best resource since it provides an updated summary of the other species as well.