FAQs on Mormyrid Fishes
Related Articles: Mormyrids, Elephantfishes, Electrogenic Fishes,
Related FAQs: Mormyrids,
Elephantfishes, Mormyrid Identification,
Mormyrid Behavior, Mormyrid Compatibility, Mormyrid Selection, Mormyrid Feeding, Mormyrid Disease, Mormyrid Reproduction, Bony Tongue Fishes, Electrogenic Fishes,
Aba Aba Knifefish, African Butterflyfish, Arapaimas, Arowanas, Featherfin Knives, New World Knifefishes,
Elephant Nose and Iron
A few weeks ago, I wrote to you about a baby elephant nose that I got
from my neighbor that I felt was extremely emaciated. He was keeping it
with quite a few tetras and rasboras and had a powerhead plus two hob
filters on the tank but was indifferent to the condition of the elephant
nose. I talked him into selling it to me, brought it home and put it in
my 10 gallon plant tank (cycled for over a year), and tried to help it.
The little elephant nose put up a valiant fight, but ultimately passed
I'm heartsick as I really fell in love with the little guy and I've been
searching your site to try to find out what I did wrong. I came across
articles in which you state that elephant nose are sensitive to iron. I
use RO/DI water (you might remember me from other posts - I live in
Idaho, have human remains in the water, among other toxic junk) and I
add Equilibrium to bring the mineral content back up. I was looking at
the bottle today and it says Equilibrium does contain iron that they
list as 0.11% Water Soluble Iron (Fe). Would that have been enough to
affect the elephant nose. Also, I used to put Excel Flourish in the tank
(though I had not added any for at least three months prior to this
incident) and it says it "...has iron reducing properties which promote
the ferrous state of Iron (Fe+2)...." Could this have harmed the little
elephant nose? My roommate wants to get a black ghost knife fish, but
now I'm worried as the BGK is a mormyrid the same as the elephant nose.
Even though we're setting
up a tank specifically catering to the needs of the BGK, with filtering
and powerheads providing more than 1,000 gph of water flow in a 72
gallon tank, I need to keep using the Equilibrium (I don't have to use
the Flourish) and
I'm afraid that if the iron in these products harmed or killed the
elephant nose that it might also harm the BGK. (Please don't
misunderstand, I think a great deal of SeaChem and love their products,
but not every product of
any manufacturer is right for every species of aquarium animal).
<I'm sorry this story had a sad ending, and thank you for trying so hard
to save this fish. The short answer is that aquarium iron supplements
are unlikely to harm this/any fish; at least, not if used as directed.
More likely, this Elephantnose was "just too far gone". They are not
easy fish to keep, as we've probably discussed before. While relatively
adaptable in terms of water chemistry, they can be finicky feeders, and
like all Mormyridae, they are acutely sensitive to chemicals like copper
and formalin widely used in aquarium medications. On top of that, being
wild-caught, it's not impossible for them to arrive infected with
parasitic worms, which means that however much they eat, they lose
weight. Deworming wild-caught fish isn't mandatory by any means, but if
a wild-caught fish
fails to thrive despite eating plenty of food, it's a good next step.
Anyway, you will find Black Ghost Knifefish very similar to
Elephantnoses in terms of care and feeding. You could probably argue
that these Knifefish and their relatives occupy the same ecological
niche that Mormyrids do in Africa. Soft substrate, micro-invertebrate
prey including worms and insect larvae, and plenty of oxygen are all on
the to-do list, while formalin and copper are just as toxic to Black
Ghosts as they are to Elephantnoses.
Given Black Ghost Knifefish don't need bright light -- they actually
prefer deep, shady conditions -- you will probably find iron-based
substrates redundant, even detrimental (they can cause algal problems in
of fast-growing plants). So I'd be taking the Excel Flourish out of the
equation, and sticking with silica sand, water worn pebbles and roots,
and so far as plants go, low-light tolerant species for the bottom
example) and an over-storey of fast-growing species like Amazon Frogbit
to keep algae under control. None of these plants needs any more iron
that the usual top-up with fertiliser added to the water every few
weeks. Cheers, Neale.>
Re: Elephant Nose and Iron
Thank you Neale, you made me feel a little better.
<Glad to have helped.>
I still wish I could have helped the little fella, but some things are just not
meant to be. I've nervously agreed to try the black ghost knife fish (my
roommate's all time most wanted fish - mine too if I can keep it healthy and
<They are nice, if demanding, fish. Not really for casual aquarists, but
certainly not impossible to keep either.>
The local store that sells them has fish that are about 3 inches long, they look
healthy, and the store owner demonstrated to me that all the BGKs in the tank
are hungrily eating blood worms.
<Good. These sound VERY small though! Not necessarily a bad thing -- especially
if they're feeding well -- but do be careful not to expose them to sudden
changes in temperature or water chemistry when you bring them home.>
I knocked down and completely re-worked my 72 bow front. I have put on a Fluval
405 canister filter (340 gph) and added two Hydor Koralia powerheads (one is
1,200 gph and the other is 850 gph). I know this is a little bit
excessive for a 72 gallon tank, but I have also put in two very large fake
plants (for hiding spaces) that hang down from the top all the way to the bottom
and I want to be sure the current is sufficient to move the water past those
<Understood. BGKs appreciate current, and overall water turnover rates around
8-10 times the volume of the tank is ideal. So anything between 500-700
gallons/hour should fine. But I would turn down the powerheads so that they
don't produce too much current. While the Fluval by itself won't be enough, the
two extra powerheads -- operating be full blast, anyway -- could be much too
much current. Use some common sense here.>
I have pool filter sand as a substrate and a smooth glass candle chimney wrapped
with a fake ivy plant for the fish to feel safe. I have placed it diagonally
across the water flow so the current inside the chimney is significantly less.
Since the fish is still very small, I've also added a small cave and a small
terracotta strawberry pot (placed diagonally to the water flow as an alternate
hiding and refuge away from the strong current). It will be the only fish in
<Might actually look into some suitable dither fish at some point.
Peaceful, medium-sized tetras would be ideal. Dither fish help bottom-dwellers
feel more secure. Some placid bottom-dwellers would be a plus, too, consuming
uneaten food. I'd choose something like Brochis catfish that handle deep water
better than Corydoras, but share with Corydoras the fact they won't steal food
too quickly, leaving your Black Ghost plenty of time to feed.>
Since I had knocked the entire tank down to the glass, I am currently recycling
it. I started back on 3/28/17 using Seachem Stability to supply the bacteria and
Mysis shrimp to feed them. As of today, my ammonia is down to zero, but my
nitrite is now quite high (> 5ppm - really super dark purple), and my nitrate
has only climbed to 40, so it will be another week, maybe two, before I can
start thinking about bringing the fish home.
I also have assurance from the fish store that I can bring the fish back to them
if it starts to show any signs that something may be wrong.
<I think in a tank this size, with such a small fish, the risk of "new tank
syndrome" after 4-6 weeks of cycling should be very low.>
They're very good and will help me to work out any problems that may come up and
will "board" the fish until I get things worked out. Or, worse comes to worse,
they will keep the fish and find it a better home if I can't make this work. My
roommate has built a large aquarium stand to support a larger tank, so we are
currently shopping for a 150 gallon tank along with appropriate filtration. I
know it is not a concern right now as the fish is still small, but I want the
big tank up, cycled, planted, and fully established before the fish needs it.
<Wise. If this were me, I'd get something else settled in first, to bed the
filter in. The Brochis for example, or failing that, a small, harmless
Loricariid catfish such as Ancistrus. Sometime to "stress test" the filter
before you add anything too delicate. Make sense?>
So, can you think of anything I've left out or forgotten?
<Hope the above helps! Neale.>
Re: Elephant Nose and Iron
Ok, will add the Brochis first, after the tank has finished cycling, if I can
find them. I did a quick search and came up with the emerald catfish (Corydoras
splendens), is that the species you were referring to?
<Yes; used to be called Corydoras splendens, then became Brochis splendens, and
now seems to have switched back. An excellent, inexpensive catfish.>
The selection of freshwater fish in my area is limited and I've never heard of
this fish before.
<Very similar to the common Bronze Catfish, Corydoras aeneus, but a bit chunkier
and with a dorsal fin that has a much longer base than on typical Corydoras.
Quite commonly traded and not expensive. Keep at least 5 specimens.>
Everyone carries the Cory Cat's, but I can't remember seeing an Emerald Catfish.
<Oh, it is out there. Should be available to order. Just make sure you
don't get it muddled with the Bronze Catfish. The dorsal fins are VERY
If I can't find one (or six to 10 as my quick Google search recommends), would 6
- 10 Congo tetra (Phenacogrammus interruptus) be appropriate or should I stick
with bottom feeders?
<Congo Tetras are excellent fish, and good companions for Black Ghost Knifefish.
They will provide good "dithering" but won't do much to clean up leftover food.>
I understand those types of tetra would appreciate the strong current and higher
oxygen levels and I know I've seen them at my fish store.
Re: Elephant Nose and Iron
Exciting news! Our new BGK is home! OMG! What a stunning fish!
Every time I walk past the tank and catch a glimpse of her, I have to stop and
watch her for a while. Anyway, things seem to be going great! I see her swimming
through the plants night and day and she seems healthy,
strong, but awfully skinny. Now, the aquarium store where I bought her had her
there for almost 3 weeks while I was cycling the tank (and I know its fully
cycled because I tested daily and watched it go from ammonia to
nitrite and then to nitrate. BEFORE I brought her home, I knew from my own
testing that the ammonia was 0, nitrite was 0, and nitrate was 5 ppm before I
went down to pick her up, but regardless of my own testing, I took a
water sample down with me and had them test to confirm my results. We were all
good. But I digress! Anyway, the aquarium store where I bought her demonstrated
to me that she was robustly eating bloodworms when I expressed concern for her
looking so thin.
<I would be tempted to deworm, using an aquarium dewormer.>
They told me that many fish arrive from the supplier in a very thin condition.
But she was with them for 3 weeks eating bloodworms and is still very skinny,
but she shows no other outward signs of any problems. Also, since I've had her
home, I've found that she LOVES Cyclops and daphnia (frozen) a lot more than
bloodworms, Mysis shrimp or catfish from the grocery store (I still include
those foods, but she ignores them until she's eaten all the Cyclops and
<Do also try newly hatched brine shrimp; these are economical and very
nutritious (unlike adult brine shrimp, which are basically popcorn for fish) if
a bit of a hassle to rear. Frozen lobster eggs are also worth trying -- some
marine aquarium stores sell them, and they're very calorie-dense, making them
useful for "fattening up" new fish.>
So now I'm in a quandary. I don't like using chemicals or medicines unless I'm
sure they're warranted, so I wanted to ask you if you believe it would be wise
to worm this fish now or give her more time (and Cyclops, and daphnia) and see
if she starts putting on some weight?
<Assuming she doesn't have worms, patience and numerous (relatively small) meals
is the best way to return fish to healthy conditions. One or two big meals is
less good than five or size small meals because fish have short digestive
tracts, so tend to poop out a lot of the food they've eaten if "overfed".
Deworming is a good idea though, such as Prazi Pro, if a fish is eating plenty
but failing to put on weight. Cheers, Neale.>
120G Elephant nose tank in planning
Hi there and thanks for WWM!
We're redoing our office and with that comes restarting a 4' 120G. My
lovely wife has let me choose the stocking and I've decided to go
with a sort of "prehistoric" African theme.
I'm planning to have it heavily
planted with low light and floating plants (easy). I may give up on the
biotope aspect and go with Val.s and floaters to keep the
lighting subdued, but I'm hoping to fill it
with plants from at least the same Continent.
I'm thinking about a group of elephant nose,
<Mmm; place all at once... they often don't get along>
group of butterflies (pair or trio), and
possibly a bichir or 2. How many of each would you stock?
<The Pantodon are fine in this size system... the Polypterus... depends
on the species>
Could some leaf fish go in there responsibly?
Any advice on substrate with the elephants in
<Fine/small and natural.>
I can't seem to find any real advice online. Most has
been just wrong based on basic research. Tank will be
over-filtered (with as muted flow as possible)
and get a 50-75% WC every 4-10 days. Feeding
will be a concern, but we currently keep a fish room with several tanks
that need live or fresh foods daily so I think we can meet that
need. This is obviously a long term (6-12 mo)
<Take your time; no hurry>
Thanks in advance for any advice and thank you for the site and
<Welcome. Bob Fenner>
Dolphin Fish, Mormyrid 1/17/14
I want to start off by saying your forum has been quite helpful over
some of my fish keeping experience. I'm always seeking knowledge on new
fish species, diseases, and all of the above and always manage to come
across your website; which always seems very wise. I have a mountain of
questions for you, however I will try to make this as to the point as
Anyways, a little over a year ago I came across the Mormyrid,
particularly the dolphin variety, and became infatuated.
<Neat animals; playful, intelligent>
I tried to gain as much knowledge on them as possible and a few months
later after being satisfied with my preparation, I started
searching for one. I looked over a year, came across a few iffy ones,
but was eventually surprised by my boss with two little dolphins waiting
for me at work (I work at a LFS.) I believe I ID'd them as Mormyrus
Kannume or Caballus, but who really knows?
<Closest is likely Fishbase.org as a taxonomic/identification resource>
I believe I have a respectable amount of knowledge on these fish now,
but was wondering if you could fill in the gaps for me, if possible. I
was given 2 dolphin at around 2" at most, one clearly more dominant than
the other. I took them both with plans to eventually either have them in
separate tanks or at least "beef" up the weaker of the two with good
care and a good diet so it was stronger for it's next home.
I've had them since the end of November and they are both still alive,
the larger being closer to 4" (at least) and fat now, and the lesser
being just slightly larger than before but the same weight except at
feeding time when they both get big round bellies. They have both been
extremely active and seem to be the happiest fish all the time. They're
in such good spirits, they volunteered to go right in my net for me when
I caught them while planting their tank for them. Very interesting fish
<Attracted to the metal likely>
My set up: 37 gallon tall (grow out tank)Trying my hand at a planted
tank Substrate is 1/2 soft soil (Mr. Aqua Water Plant Soil)
with gravel underneath (chose to reverse substrates and not cap for
dolphins delicate noses) and the other 1/2 is fine natural colored sand.
Driftwood with java moss attached rock cave Hairgrass3 sword plants3
bundles of mixed plants1 moss ball
Temperature is kept on the warm side between 80-82F degrees50g sponge
filter (though might be changing filtration soon) Additional airstone in
4 apple snail tank mates, 1 egg sac currently present at the surface. 3
Otocinclus (just added)1 Dwarf Gourami (just added)
Dolphin Diet (fed before bed time, but will eat any time of the
day):Live black worms (cleaned nightly)
Will not touch: Any pellets (of course)Frozen brine shrimp
Water changes were weekly/bi weekly 25%-45% but these guys seem to
have an issue with either my tap or my dechlorinator (SeaChem prime) so
against my nagging desire to be fastidious, I've lowered the water
changes to when it's needed since the planted tank seems to take care of
a lot on it's own.
<Best to store all make-up, change-out water for a week or more ahead of
time of use>
I'm looking into getting an RO system at home to fix this dilemma for me
so I can clean more often without worrying about irritating the fish.
I have added 3 Otocinclus (monitored for sucking on other fish) to clean
the algae and 1 dwarf Gourami to get the bugs since apparently these
things are more common in planted tanks. After reading about dwarf
gouramis on your page though, I'm rethinking my pest control choice. I
also starting dipping my plants in hydrogen peroxide before adding since
I thought this was a better choice than bleach.
<Alum is even better... search the Net, books re its use here>
Water parameters currently:Temp: 82-83F, it's a bit warm here in
<Not to worry. Periodic forays into the upper eighties F. are not a
PH: 6.8 ishNitrite: 00ppmNitrate: 20ppmAmmonia: 00pmKH: 40ppmGH: 180ppm
My questions for you:*What other food options can I do for these fish?
<Anything "meaty" of size... e.g. Tubificids... frozen/defrosted better
than live; may take some dried>
And has their nutrition been met so far or do I need to add something
else? *What is the average breathing rate of these fish? I've noticed
since day 1 that they seem to breath extremely fast. Should I consider
this their normal rate, or is this something I should have been paying
*Are there dechlorinators that are known to be better for these types of
<Mmm, yes... the Kordon (NovAqua, Amquel) and SeaChem product lines are
I do not have the option of having my water sit for a week before adding
it to the tank. Nor is it practical for me to have 20 gallons premixed
and then added to the tank as I'm a 5'1 female and am battling chronic
<Ahh, understood... and sorry for your health issues. The RO mixed will
help tremendously here>
*Will these fish be ok if supplements are added correctly? i.e. adding
SeaChem Flourish and/or excel? *Will adding pressurized C02 be ok if I
had an indicator monitoring it?
<These additions; as you state, added properly, will be fine>
*I noticed the dolphins being a bit lazier, not swimming wildly (but
happily) around the tank all the time. Is this due to comfort?
<Are fine; "happy" as you state, when out and about searching, curious
re their world, interacting w/ each other>
The smaller hides when it can and usually only comes out when being
chased or when it's dinner time, but the larger isn't as ruthless and
chasing the smaller so often, so it's not showing itself as often. The
larger one, and one I can see resting since it's too large to hide under
things, is still active and noses through the soil quite often. It has
bursts of energy or times of the day, but I see it resting on the bottom
sometimes now. This might be normal for most fish to "nap" but I've not
seen this much before now with them. It is possible they are growing
more accustom to me and don't swim erratically when I come to watch them
now, but I'm unsure if it could be something more serious. The larger
dolphin used to tear at the smaller one's fins all the time, but now
they're completely healed and intact. Is this mercy or a sign of more
ominous issues occurring in the tank?
<Mormyrids often don't "get along" in the same, smaller volumes... will
do so temporarily if crowded... You may find that the larger one will
calm down if given a "shelter"... can be a tube of PVC, glass chimney or
such (i.e. clear/transparent) or not. Otherwise; best to have these fish
in two separate systems>
Attached are some photos.#1-week 1 of having them both#2-12/14 of larger
dolphin#3-today, larger dolphin. excuse the water spots#4-today, larger
dolphin#5-today, larger dolphin. Most important to show, I noticed some
dark spots on the fins of this fish. There is no ammonia present, but I
also just did a water change 2 days ago. The white specs seen are not on
the actual fish but on glass (hence the Gourami, still getting used to
the critters associated with more planted tanks) this is the "resting" I
was speaking about.
Thank you for your time and patience reading through this, I wanted to
be thorough as possible. I've got a 125g and a 240g as well and these
are just my babies. It took so long to get them and I want to make sure
they are cared for properly, though I'm a bit overbearing when it comes
to these two. Looking forward to hearing from you.
Have a great night! Lauren Saunders
<Thank you for sharing. Bob Fenner>
Re: Dolphin Fish, Mormyrid; hlth., sys., fdg f's
Hello again WWM Crew!
Thanks for your response, I really appreciate it! I am actually having a
dilemma with the dolphin, though I'm not sure if it's serious. As stated
before, I noticed less activity with these dolphins. What concerns me is
that now it seems like the larger dolphin is breathing differently when
sitting at the bottom on the tank. I asked before about the breathing rate
of this fish because it seemed like they naturally had a very fast rate.
<Yes; agreed. Some 90 gill movements per minute is not unusual in my
The worry I have now is that the dolphin is having trouble breathing. It
seems to be gasping so instead of a steady constant movement of the gills,
it stops then they flap a few times, then stops again.
<Not good. Water changes, activated carbon, PolyFilter or such I'd be adding
to the filter, water movement path>
The mouth also seems to be opening and closing with this, which I've never
seen it do. I also noticed besides the inactivity and breathing issue that
there looks like a few little bumps on the side of the larger dolphin. They
don't look like Ich or have any color, they look like they are part of the
<Still.... worrisome. S/b smooth>
I've continued to add more plants to the tank, but I'm unsure if the two
correlate. I have a 50g sponge filter as of right now, and was turning down
the intensity occasionally due to the air pump making a horribly loud hum;
but I don't know if this is the culprit as I have kept it going at full
strength since I noticed this problem and it seems to continue.
<You do have other filtration and water movement I hope/trust. I'd be adding
more... outside power filtration; hang on and/or canister>
I am heading into work today to replace it as well as getting a new
sandstone/airstone to see if that helps. I noticed some very mild flashing
about a week ago so after a w/c and plant trimming I added a low dose of
Seachem Stressguard and Seachem Stability since I cleaned the sponge filter
also. I rinsed the sponge filter with tank water to make sure I didn't
kill any bacteria, but when I turned the filter on a cloud of dust came out
of it. I waited 2 hours after cleaning the filter before I did my water
change/trimming and did not notice any stress from the fish. The only odd
thing I did notice that was different about this w/c was that the water had
an unusual amount of air bubbles in it making everything look foggy. I
discussed it with my fiancé and I suspect that the water may have been
cooler than the tank water, though he swore that it was warmer. The bubbles
made the tank look milky and the ottos were covered in bubbles afterwards.
Is it possible that the bumps came from the air bubbles? I'm unsure if the
products I used were a problem either seeing that both are extremely mild
and have been used before. The itching is only occasionally, but it's enough
to have me concerned.
<Me too... Act, now; re the above stmt.s>
They both still have moments of activity and do swim about chasing their
tankmates and they both have healthy appetites. I've got different foods as
stated before, but I've mostly been feeding live black worms. They seem to
be doing VERY well off of it and are both a healthy weight. Even the smaller
dolphin who looked frail and skinny, is starting to put on actual weight and
looks wonderful, though still tiny compared to the other. I keep the black
worms clean with a nightly cleaning before I feed them and don't seem to
have any losses with them. Even though I seem to have great results off of
blackworms, I'm aware that they can hold parasites
<Not really if they're cultured (vs. wild-collected). Ask your supplier re,
or wean them on to frozen/defrosted meaty foods (rinsed ahead of offering)>
so I'm wondering if there's a way to ensure my worms are parasite free i.e.
rinsing in Epsom salts or something; or is it safe to PraziPro these fish if
I did see any infection?
<I would not>
I'm looking into culturing my own live worms such as white worms as well,
hoping to try to reduce risk as much as possible.
Just did a quick strip test a moment ago
My temp is 79F Ph: 6.8-7.0Nitrate: .10ppm-20ppmNitrite: 0ppmKH: 40ppmGH:
Ammonia: 0ppm (did API vial test)
linking 2 videos from my photobucket of examples of the breathing, the
smaller dolphin flashing, and hopefully you can see the bumps though they
are near impossible to pick up on my phone. I saw some white specks on the
larger dolphin in the videos, but I believe they were from the sand since
they weren't consistently there even an hour before or an hour after. Black
spot still on the dorsal, and attached photo of the small bumps, forgive me
if they are hard to see, I could barely make them out in the photos but they
look like "chicken skin" like humans get. The white blobs in the photo are
baby apple snails. Excuse the messiness of my tank, they kick up the soil
onto the sand and I haven't planted the new plants, leaving algae for ottos
and baby snails.
Thank you again for your time and I hope you'll be able to answer some of my
<Do please keep us informed. Bob Fenner>
Re: Dolphin Fish, Mormyrid 2/2/14
Hi WWM Crew and Mr. Fenner,
As of right now I only have the 50g sponge filter on this tank,
<Ahh! I definitely WOULD be upgrading, at least adding a good sized outside
power filter here. The improvement in water quality, reduction in
maintenance will be discernible>
I haven't been a huge fan of it's bulkiness but didn't realize it was a
problem since my water parameters have always tested well. I'm going to take
off one of my Eheim canister filters (80 gallon) from my 125gallon tank then
tonight. I'm going clean the entire filter with bleach then have it run
overnight in heavily dechlorinated water (prime) in a 5 gallon bucket as a
precautionary since I don't want to mix equipment between tanks.
<You are wise here>
I'll run both the sponge filter and the canister until I've got the canister
seeded enough. If the problem was indeed a filtration issue, I'll gladly
purchase a more suitable filter if necessary.
<Eheim's are excellent. I use them; have used them for decades, personally
I'm keeping my fingers crossed that this was the issue. In the meantime,
do you have any solutions to "disinfecting" my live blackworms?
<The continuous, long-term (hours) rinsing in slow, cold tapwater is about
all I would do>
I always grab my worms from fresh stock that just arrives and I clean them
nightly, but I doubt that it's enough to not be at risk still. I'm going to
speak directly to my wholesaler to see how they cultivate their stock, but
I'm weary knowing that PraziPro isn't an option if they have a bad batch.
I'll keep you posted, thanks again!
Have a wonderful evening, Lauren Saunders
<And you Lauren. Bob Fenner>
Re: Dolphin Fish, Mormyrid; hlth.
Hello Mr. Fenner and crew!
Giving you an update on the tank. After 15 minutes of running in bleach
water, 24 hours of running in heavily dechlorinated water, followed by a
thorough rinsing; I added the 80g Eheim canister filter to my tank. The
fish seemed fine with it for a few days, but now 2 ottocinclus just died
leaving me with one,
<The genus Otocinclus members are social... live in shoals>
though they stopped cleaning the algae and glass 2 weeks ago,
<? Something wrong here... low DO?>
unsure of the cause. Dolphin do seem more active though they always were
for the most part, but I still catch the larger resting on the bottom on
occasion, hard to tell with the smaller since it hides under the
driftwood when it's not searching for worms. The breathing rate doesn't
look as labored, but it is still an on and off motion (hard to explain)
rather than a constant flutter of the gills, though I did see similar
breathing patterns of dolphins via YouTube. Unsure which is the normal
pattern at this point. There are still weird discolorations on the skin
of the dolphin, unsure of the cause or if it's possible the otto's were
sucking on their skin.
I noticed the ottos "attacking" when I had first gotten them, but haven't
seen it happening recently. Found it unusual since I thought this wasn't
a typical behavior of the otto. Haven't witness any flashing from the
dolphin, but did see my blue gourami flash against the filter once last
night. Appetites are still healthy.
Water test: Nitrates: 10ppmNitrites: 0ppmPh: 6.8KH: 40ppmGH:
Will keep you updated if anything changes, but unsure if there's
anything I should be doing at this point. Doing my best not to mettle as
much as possible.
Have a wonderful day! Lauren
<And you. B>
Reply to old
answer, Mormyrid beh. 1/25/11
Hi, a while ago I was asking you guys for some tips on my extremely shy
<A very unusual Elephantnose fish a nice
It's been a couple months, and he/she has become extremely
comfortable in his/her aquarium and now is always out and will even eat
out of my hand.
<Excellent. Yes, Elephantnoses can become very tame, and once tame,
are easier to feed than when first purchased. They are supposedly among
the most "brainy" fish and their behaviour in captivity is
often remarkably trusting and playful.>
I bought a large Anubias sp. plant that fills the tank from corner to
corner and have a layer of duckweed on the top and I feel the lack of
wide and open spaces in the tank makes the fish feel more
<I would agree 100%. While many aquarists see Duckweed as a pest, it
can be hugely useful in tanks where the fish dislike bright
This isn't a question, but just my experience with the fish and I
hope it helps you guys out.
<Thanks very much for sending this along.>
And thanks for the great website! It is definitely one of my top
sources when deciding on fish!
<Glad you enjoy the site, and thanks for the kind words. Cheers,
Anableps anableps. Mormyrids, not brackish f' as well
Sorry to be a nag but I have one final question :) What is the salt
tolerance of Peter's Elephant Nose Fish?
<Nil. They are textbook examples of primary freshwater fish with
little to no tolerance of saline conditions.>
I do NOT have one but am interested in possibly getting one for this
tank as well as a final tankmate.
<Good. Gnathonemus petersii, and indeed Mormyrids generally, are
very difficult to maintain, and you absolutely must research their
needs carefully before purchase. Do see here:
You're looking at a tank with a sandy substrate, no bottom-feeding
competitors (like Loaches!), plenty of floating plants, and water of
very good quality. Water chemistry isn't critical, but certainly
I am aware of their unique feeding requirements etc... and can satisfy
Just wondering if you think they'd be able to handle this
<Not really, no. In any case, suspect you'll have your hands
full with the Anableps. If you want other fish, look at Mollies, Limia,
perhaps Mudskippers (though probably not the super-aggressive P.
Flounders/soles might work, but not with the loaches. Cheers,
nose fish... sys., comp. 4/4/08 I was thinking
about getting a ten gallon tank. I want to put an Elephant nose fish in
the tank, some angel fish, and maybe a small bristle nose Pleco and/or
some bottom feeders maybe some Cory cats or clown loaches. What do you
think of this grouping of fish? Thank you. Nick <Hi Nick. In a word,
NO! This combination of fish won't work. Starting at the top:
Gnathonemus petersi is one of the most difficult fish in the hobby to
maintain for any length of time. These things are non-negotiable: a
sandy substrate, excellent water quality, live or wet frozen foods
(bloodworms particularly), and no bottom-feeding tankmates. Most
specimens starve to death, so you have to consider feeding carefully.
Secondly, Angelfish and Clown Loaches and Bristlenose Plecs are all far
too large for a 10 gallon tank. A pair of Angels might fit into a 30
gallon tank along with a few midwater fish, but Clowns need to be kept
in groups (at least three specimens) and ultimately need tanks 55
gallons upwards. Both Clown Loaches and Gnathonemus petersi are
super-sensitive to copper-based medications, and Gnathonemus petersi
especially will be quickly killed by the standard anti-Ick medications.
So before thinking about tankmates for this fish, you need to have a
quarantine tank set up. For a 10-gallon tank, you really need to be
thinking about small, inactive fish around the 1 to 1.5 inch mark.
Shrimps and Nerite snails are also worth considering. If you're a
beginner, steer clear of 10-gallon tanks entirely; they're
difficult to stock and even more difficult to maintain. For
inexperienced aquarists, the 20-gallon tank is the ABSOLUTE minimum.
Hope this helps, Neale.>
Skinny elephant nose I hope you can help me, I bought a
elephant nose 3 wks ago. and he was doing fine, but lately he is not
eating. I feed him blood worms at night, so that my Angel fish
can't see it, but the cat fish go at it and my CAE, so leaves
nothing for the elephant fish. <Sounds like it is mixed in with
incompatible tankmates> I have tried many ways of trying to feed
him, I have placed it in the ghost tube, which he doesn't go in it
any ways, which I don't know how to coax him in there. I have tried
with a turkey baster and he would swim away, he has eaten a little bit,
but not enough he is starting to look skinny, I hope you can help me
before he dies. <I would move this fish to more suitable quarters.
Now. Bob Fenner> Thanks, Shelley Mr. Fenner, RE: your article
"The Elephantfishes, family Mormyridae, In
Aquariums" on the: http://www.wetwebmedia.com/FWSubWebIndex/mormyrids.htm
website... I just wanted to say I thoroughly enjoyed
reading your superbly informative article about the
Mormyrids. I grew up a fish buff but was not able to
maintain my aquariums while in college. However, I have been
bitten by the fish bug once again. <Ahh, welcome back "to the
fold"> I've got a 55 set up with some Congo Tetras, Clown
Loaches, and soon some baby Royal Plecos. I was thinking of
adding some Elephantnose fish. However, I noticed you wrote
they inhabit muddy waters in the wild. <Yes> I have a
lot of filtration on my tank. A lot of driftwood and lava
rock too... stacked up to the top with java moss
everywhere. But, the water moves a lot. Do you
think Elephantnose fish would do okay in moving water? <Yes...
though the water will likely be much clearer, more vigorous in
movement, these are adaptable fishes. They will greatly enjoy your
driftwood and Java Moss>> I've got 2 Hagen 400
and one Hagen 802 (?) powerheads, one of the larger small Eheims, a
supreme AquaMaster and some air hooked up to an undergravel
filter... all blowing the water counterclockwise as I am
north of the equator. <I see. No problem> Wet-dry
filter, carbon, peat moss, 6.5-7.0 pH, 80 degrees F. So, the
thing to do is please let me know if you think Elephantnose fish would
be okay in my turbulent setup. Thanks in advance for your
time. Sincerely, Dr. Gregory Findura <If you can locate
all the specimens that you intend to keep, do place them all at once to
lessen the likelihood of interspecific aggression. Oh, and please do
write back and tell us how they are doing. Bob Fenner>
Re: Wallaby wood Thanks for the quick reply. The specimen
marketed under the name "wallaby wood" was purchased at my
LFS, my research seems to suggest that it is actually Swahala wood from
the dark reaches of mighty Africa. <Ahh, I do know this product>
Nobody at different LFS stores seem to know much about it although they
all stock and sell it. Their instructions are all similar, just soak in
hot water for 1-2 days and it will be fine, no staining of water and if
there is any, well the filtration system will clear it up. Well 8 days
later of soaking and boiling it in my huge lobster pot still produces a
beautiful light brown water which would make any ice tea company proud!
Thank you for your input, I will not give up, sodium bicarbonate is
next. Quick follow-up on one of my earlier ?'s regarding sexing of
the Mormyrid "elephant nose fish", after researching
bibliography came across small paragraph stating that "the fish
with the more curved anal fin is the male". Just thought you may
like to know. Thanks again Stephen <Thank you for this. Have heard
similar statements. Bob Fenner>
Freshwater fish electro-sense question I recently bought an
elephant fish. today my girlfriend surprised me with a black ghost
knife. They are both about 3in and are in a 34 gallon tank with
separate very good hiding spots. will there 'electro-senses'
clash? < There have been some studies on these electromagnetic
fields generated by these fish but not much in the popular aquarium
literature. But I am sure that they are aware of each other.> also
how sensitive are they to salt? < These fish come from clean warm
acidic water and have become very sensitive to salt.-Chuck> I use a
little less then the recommended dose of aquarium salt (1tbsp per 5
gallon). tank also includes 6 glass cats and a blue lobster. thanks for
your time. -Zac
|Elephantnose project Mr. Fenner, <Hello
there> My friend and I have decided to do our science fair
project about Elephantnoses. After experimentation I wish to keep
them as pets. I have sent the details of the project in the
attachment. I was wondering if you could look it over and give any
feedback. <Interesting experiment. Might I ask, how do you
intend to produce your electromagnetic field? How to measure
it?> In no way do I wish to cause the fish and harm or distress.
I want them to be as comfortable in their environment as physically
possible. <Mmm, this will not happen in your model... Mormyrids
(and other electrogenic fishes) are "driven crazy" by
even the introduction of electrical conductive (metal) materials in
their systems... as you will find> Right now I have 5
Elephantnoses in a 55 gallon tank. They seem to be territorial but
not attacking one another aggressively. <You are likely
"right at" some maximum number... they can be crowded
temporarily at much higher densities, but don't "get
along" at about more than one per twenty, thirty gallons at
"adult" size> Usually they lightly bump into one
another and like to swim around the tank in a group. I am very
persistent about water conditions and check them everyday. If there
are any particular products that work well and are not toxic to the
Elephantnoses that you feel are useful, I would really appreciate
any suggestions. <It appears they are doing well in your
care> These are some of the most magnificent and intriguing fish
I have ever encountered. They are curious and playful like none
others I have seen. <And some of the most intelligent fishes...
as gauged by the relative size, shape of their brains. Bob
Fenner> Brandi Alderson
What effect does varying strengths of electromagnetic field
have on the behaviour of Elephant Noses?
It is believed that the higher the strength of the
electromagnetic field, the more confused the fish will be.
This will cause them to retreat and hide.
We will observe the fish for a half hour each day
for 5 days, videotape and log each observation, without
subjecting them to any change. We will then, once a day, subject
the fish to an electromagnetic field of increasing strength. The
increasing magnetic field will not produce any direct effect in
the fish. However, when they move, the magnetic field should
distort the electrical pulses the fish themselves emit. This may
cause them to see things that arent there. We will then study the
fishs responses to this field. It might confuse the fish, but
shouldnt harm them in any way. No non-vertebrates fit our
requirements as an electromagnetic emitting and sensing organism
with observable social behaviour. We will not be electrifying the
fish and will discontinue the experiment if the fish show obvious
signs of discomfort or exhibit potentially hazardous
Elephant Nose Fish for Sale [online]. 2003. [cited 8/21/03].
Available from World Wide Web:
Aquazoo. Elephant Nose [online]. 2000. [cited 9/2/03].
Available from World Wide Web:
Corporation. Proper Feeding of Your Aquarium Fish [online].
[cited 9/2/03]. Available from World Wide Web: <URL:
Robert, Fenner. The Elephantfishes, family Mormyridae, In
Aquariums [online]. [cited 9/2/03]. Available from the World Wide
ILAR Journal. Behavioural
Research Outside the Laboratory [online]. 1996 [cited 9/8/03].
Available from World Wide Web:
Ulrich. Translated by Kimber, Rita and Robert. Loaches, Flying
Foxes and Elephant-trunk Fishes. Aquarium Fish. Barrons
Educational Series, Inc. Hong Kong, 1992.
Joseph S. The Complete Fishkeeper: Everything Aquarium Fishes
Need to Stay Happy, Healthy, and Alive, William Morrow and
Company, Inc. New York, New York. 1991.