Columbian (Silver-Tipped) Shark  7/1/05
Hi,
<Hi, Pufferpunk here>
Sorry to ask a question with an answer that may be obvious to some but it's necessary.  I have been reading your site and it's definitely helpful, although I am still a bit confused on the right road for these "sharks".  Mine (two of them) are around 5" in length, and they just moved (as in TODAY) from a 10-gallon to a 55-gallon.  
<Much better!>
Now, before you yell at me, I have to defend myself by telling you that I bought them on a whim at Wal-Mart and had no idea that they'd get so big.  
<Research before buying next time but I guess I don't have to tell you that now.>
So, since I was waiting on a hand-me-down 55 from my friend, the sharks resided in a way-too-small 10.  In this 10-gallon, they were starting to get very uncomfortable, I know and swam weird patterns, I suspect because they were so big and didn't have hardly any swimming space.  Now that they're moved, they don't seem to be
happier.. I read about fish coming from tanks too small that hang on the bottom for a while or maybe it's the relocation that has them confused.  They seemed to be swimming more as of a minute ago but they were just lying on the bottom together, looking out the front.  
<Maybe they were franticly looking for more swimming room in the smaller tank.  Now that they have the room, they can take the well-deserved rest.>
I should also comment on their water.  As these were fish-whims, they were always in freshwater with regular aquarium salt and up until a few months ago I had no idea they were supposed to be transitioned to brackish or saltwater.  I guess my question is, after you hopefully give some answers to the questions posed already in this run-on query, are they supposed to END UP brackish or completely saltwater?  I have read that you are supposed to "slowly add more salt" but for a 55-gallon, how much and how often?  
<You'll need marine salt & a hydrometer to measure it.  Start raising the SG (specific gravity, measured by a hydrometer), .002/weekly water change, until you reach around 1.010-12.  Eventually, as they grow to 14-18", they will need a much bigger tank & marine conditions (1.020-24).  You should premix the salt in a bucket, before adding.  It'll take some math to figure all this out.>
Also, can other types of sharks live in this water, whatever it ends up?  
<The sharks you have, are the only BW "sharks".  Since they are actually schooling fish, more sharks would be welcome but you are talking about eventually a huge (50g ea) tank!  I'm sorry these fish are even sold at most LFS, as there are very few folks willing to house these fish properly for life.  Most will die a slow, miserable, stunted death...>
The person at the pet store told me that any semi-aggressive can go with any other semi-aggressive and I'm guessing that's not the case.  
<These fish are not aggressive at all but are predatory & will eat anything they can fit into their mouths.  They are constantly on the move (most of the time), so they cannot be housed with mellow, shy, slow-moving fish--the sharks will stress them out & outcompete them for food.>
Should I choose tankmates, if I upgrade to a bigger tank, based on water as well as compatibility?
<Yes, pick BW fish that will eventually transition to SW as adults.  More of the same species sharks & scats would work well, but again, figure eventually needing 50g/fish.  A school of these sharks can be quite impressive!  ~PP>
Thanks, Kate

Killer Catfish?
Thank you! You really put my mind at ease. I love my 3 aquariums even if they got a little neglected when I had a baby last August (never to the point of bad water or disrepair, just not as diligent as I had been). Now that I am turning my attention fully back to my aquatic pets, I have one more question and I'll leave you alone. I have done a lot of research on this, but haven't come to a conclusion. I have an unplanted 55 gallon tank with two 330 Penguin BioWheel filters with a 4.5 year old silver tip shark catfish (Mack the Knife) and a large Pleco (Rainbow Barrone, Jr.). He had been coexisting with one Oscar who succumbed to old age. My husband was pretty heartbroken by Salvador the Oscar dying, so he didn't want another one. I got a Jack Dempsey, but Mack apparently killed him one night in a territory dispute. Short story long, is there any other species that would be compatible with Mack, or should I just leave him and Rainbow in there alone?
< If Mack is going to kill all the new fish then I think leaving him alone is the best way to go> 
Also, I've noticed Rainbow sucking on Mack lately. Is this a harmful practice? Should I separate them? Mack doesn't seem to mind as he just lays there. Thanks again!
< Plecos have mouth parts for scrapping algae of things like rocks and wood. They will also scrape the protective slime off fish and can be a problem for fish like discus and angels. Little Cory cats on the other hand are just looking for bits of left over food and are harmless.-Chuck>

Iridescent sharks flipping out
Hello, My name is Ted and I'm from NJ. This is the first time I'm submitting a question on this site though I've been on it many times. I think you guys are awesome and really appreciate all of your help and knowledge that you share. Thank you. 
Ok, here's my problem.  I have two quite large iridescent sharks, one about 9" and the other about 12". I have recently moved them into a 72 gallon bowed front tank. Health wise they seem to be doing fine but they are getting spooked very easily. I've been leaving a couple of bags of gravel on top of the canopy because I'm afraid that I'm going to find one on the floor one day.
<Good move>
I have a feeling that being that its a bowed front that any outside objects or light might be making them flip out.
<Possible>
I never had a problem with them in their last tank. Though they were with other fish, and the tank was highly over stocked. (the two sharks, an Arowana, a parrot, a silver dollar, a Pleco, a clown loach, and a golden algae eater in a 90g) Obviously you can see why I moved them. I don't know, maybe its the tank, or maybe its the lack of aquatic friends. What do you make of it?
<Mmm, the crowding and shape of this tank are problematical, but the worst trouble here is that these catfishes at this size are generally marine... Please read here: http://wetwebmedia.com/ariidcats.htm and the related FAQs linked above. Bob Fenner>

Arius after all
Nope it is a "catfish" shark, silver tipped shark.  Anyway I took it back
to the pet store since another one died and I didn't want to have it on my
conscious that I am a fish killer  :)  Thanks anyway
<Thank you... will add this common name to our ariid catfish section so the search tool will find it hence. Bob Fenner>

Columbian Shark Needs Friends  4/25/05
<Hi, Pufferpunk here>
I have a question about my aquarium. It is 20 gallons now but will be upgraded as needed within a year. The only fish in the tank is one very friendly Columbian shark named Antonio. The poor guy wants a buddy; I'm sure by the way he follows my finger against the glass. The problem is if we get another Columbian we won't know who is who. Is there another catfish or shark species that will keep Antonio company while the tank slowly shifts to full saltwater?
<since Antonio is actually a schooling species, he would be happiest with more of his same kind.>  
Perhaps a mail order outfit is available for other brackish catsharks? If the only species available are Columbian sharks, would a molly, orange Chromides or similar mid-water community type fish keep our little Columbian boy company? That is until Antonio eats this smaller fish! Thank you.
<I'm glad you are planning on an upgrade in tank size & marine conditions.  A school of 18" silver sharks can be quite an impressive sight on their own!  Just make sure the tank is big enough.  ~PP>

Columbian shark
Hi, my name is Chris,
<Hello, my name is Bob>
I have recently purchase a Columbian shark for my 65 gallon aquarium.  My question is that all day he swims the same pattern around the top of my tank, is this normal for him to do?
<Yes, a very active catfish>
My sg is 1.007, ph is 8.2, water temp is 79, nitrites, nitrates, and ammonia is 0, and phosphates is 1.0.  Other tank mates are: 5 African cichlids, 2 blood parrots, 1 scat, 1 Mono Argenteus and one tiger barb.  Any help would be appreciated.  
<Help with? Your cichlids may not "like" the salt content indefinitely. Please read here: http://www.wetwebmedia.com/ariidcats.htm
and the Related FAQs (linked above).
Bob Fenner>

Iridescent shark care
I was recently given a 39 gallon tank with four fish. I'm not sure what the
smaller 2 fish are. They are about 3 inches long and are flat (like an
angelfish) and white with very light gray stripes. They also have a "feeler." I
haven't been able to id them.
<Sound like some sort of gourami... Do take a look here: http://www.wetwebmedia.com/FWSubWebIndex/anabantoids.htm>
The former owner told me the other two were Bala sharks but, from looking at
pictures I believe that they are older Iridescent sharks. Their heads almost
look like hammerheads and they are black with a silver stripe down their sides
with a whitish underbelly. They are approx. 7-9 inches long. (although one
has no tail fin, I was told another fish attacked it and ate it off).  I have no
knowledge of fish but no one else would take them. When we received the tank
it had a layer of slime around the inside of the tank, and the filter was
filthy and needed immediate replacement. We have cleaned the tank and replaced the
filter, but now what do we do to get/keep these fish healthy?
<Study... read... I'd suggest having a petfish friend come by first and help you actually identify your livestock to species... Then you can look up their individual care requirements>
The former
owner gave us stress coat and algae destroyer to add to the water.
<I'd leave off with this last product... toxic to all>
She was feeding
them TetraColor Tropical flakes. Are these the appropriate things to be
using?
<The food is fine... but you should enlarge the selection>
I have read that the sharks prefer more than 2 but these 2 have been
together for a while and appear to be fine with just the 2 of them. They also seem to
have calmed down from the move. They are peacefully swimming and do not freak
out if I approach the tank. However, when we got them one of sharks has a
swollen spot on his nose with a red spot in the center of it. So my question is
this what do I need to do to provide these fish with a long healthy life? I am
a complete novice, but everyone knows that I will take in an abandoned animal.
Thanks for any help you can provide me with.
Tia
<Need to know the actual species... Are these your sharks: http://www.wetwebmedia.com/ariidcats.htm
Bob Fenner>

Silver shark cats, WWM
I had 3 silver shark cats and eventually 2 died off. The last 1, which I had the longest, was acting weird when the 2 one died and I was wonder if he needs to be in groups or not? The second question I have is do they need to be in salt water? I really need your help.
Thanks, Ethan
<Read here: http://www.wetwebmedia.com/ariidcats.htm
and the files above in blue. Bob Fenner>

Arius seemanni please help!
Hi!  My name is Rebekah and my husband's name is Chris.
<My name is Paul Maud'dib... actually, call me Bob>
We got a  10 gallon
fish tank over a year ago and our first two fish were Arius seemanni,  or shark
catfish.  No one told us they would get so big, we were new at  this!  We
just got them a 29 gallon tank.  They were both doing very  well and very
active.  They seem like best friends and always swim with  each other.  Tonight we
were horrified to look in our tank and see one of  our shark fish dying!
<!>
We had to leave and when we came back he was dead, absolute stiff as a  
board.  The other shark left seems quite sad.  Our question is what  happened?  He
was so healthy and active!  We don't want to lose our  other shark.  Let me
tell you the symptoms and I hope you can help!
My husband heard a loud commotion in our tank and saw the catfish really  
freaking out.  He was shooting around the tank at lightening speeds!   Then he
started to convulse and swim upside down and his mouth kept opening and  closing
and he almost seemed to be gasping for air.  It didn't take him  long to die.
He turned really white and the tips of his black fins turned  almost a clear
white.  Like I said, he was very stiff when we removed  him.  
<Frightening>
Where did we go wrong?  We were so sad to loose one of our first fish  we
ever bought!  And does the other catfish need a friend to replace the  dead one?  
Thank you so much for any help!
Bekah and Chris
<Some sort of catastrophic injury happened to just the one specimen... Likely it either crashed into part of the decor or rammed up into the hood/top... this does happen... more so in smaller systems than larger. Bob Fenner>

Columbian sharks
Dear crew I would be very grateful for some advice. I have two Columbian  
sharks which are about 5" long, just recently one has started just lying on the  
gravel a lot it also has a very large belly. Should I be concerned.
   The water is fine & although it is a fresh water tank I  add one teaspoon
of salt for every two gallons of water in a 90 gallon  tank.
                    happy new year
                            James
<James, I would add some Epsom Salt (magnesium sulfate), at one teaspoon per five gallons here, in the hope it will alleviate the swelling. I also encourage you to get/use a hydrometer... to measure the specific gravity of the water... I do hope your other livestock can tolerate brackish water... and that you have plans to graduate these catfish to full marine in future. Bob Fenner>

Columbian Shark Question
I have 3 Columbian sharks, about 4 inches in a 29 gal. tank.  I've done a
lot of reading on forums such as this about them and thought I was doing
things well.  I just recently did a water change and changes some of the
tank decor to make more room for them.  Now I just noticed one of them has a
white, growth looking spot on his tail fin. <Possibly fin and tail rot?>  They usually lay on the ground from time to time but now they do it A LOT.  I'm guessing that that is just because they are getting used to their new surroundings.  But I have no idea about the white, growth looking thing.  Any help would be great.  <I suggest you check out the saltwater FAQs. My best guess is that it might be Lymphocystis  see the picture here to see if maybe that's what it is? http://www.wetwebmedia.com/viraldislymph.htm. If it is there are FAQs to tell you how to handle it or write back and we will work you out a game plan Adam. Good luck, MacL>
Thanks
Adam

Columbian sharks and other large fishes for display 11/9/04
Hi Bob.
<Anthony Calfo in his stead>
Two questions for ya. First, I was wondering if I could put two
Groupers a Lionfish and a Puffer in a 125 gal?
<assuming you are looking at the popular varieties (porcupine/dogface puffers, volitans lion, large groupers like panther, etc), then no... this is way too much regardless of filtration. The sheer adult size (or not if they stunt and die prematurely for being crowded) of these fishes makes all in this one tank inappropriate, if even possible. Do look through our archives and on databases like fishbase.org to see and consider the adult sizes of the fishes you with to keep. Now... if you are willing to go for "dwarf" varieties of the above mentioned, there are indeed species of small adult length at maturity that will work here>
Second, could I put two Columbian sharks with them?
<one would not even fit... these fishes start life as fresh/brackish and may end up at sea (coastal) but get quite large (2 foot range) and yet are no match for the toothy predators - they will get mauled. Above all... this tank is too small for so many large fishes to he kept healthy/humanely>
Brandon Zimmerman
<do research some more, my friend... there are species to appeal and suit you here to be found. Anthony>

Columbian Sharks and Java Ferns
Sorry to bother you guys again, but I have two questions I couldn't find on your site. I have two Columbian sharks. They are both still pretty young (about 5 inches). <You'll need about 100 gallons of brackish water to keep these large fish into adulthood.> I've noticed recently that their fins are a little torn, the smaller shark more than the bigger one. I doesn't look at all like it could be fin and tail rot, besides they are both really healthy. They are inseparable and I've never seen them be violent to one another, I was wondering if they could be doing this to themselves since they are the most aggressive fish in the tank. <Possible> (33 gal with the two sharks, pleco, African leaf fish, leopard leaf fish and fire eel) <The eel may be causing a ruckus at night> Don't worry we are eventually moving the sharks to a brackish tank. <Salt will help heal as well as start adjusting them to their adult requirements. Host of reasons for tattered fins. Aggression, very high or low pH, ammonia, very high nitrates etc..> Second question, we have sand as our substrate and have live plants I think they are java ferns. The pet store told us that if the plants are submerged directly into the sand eventually they will start emitting toxic gases that are undetectable and will kill our fish. Because of this I put the plants in little plastic cups filled with gravel and submerged those in the sand. <Will not help> I was just wondering if this was necessary. I couldn't find any info on the net. <Java Fern grows from a "stem" that grows horizontal to the substrate. The fronds then grow up along this stem. If it is buried in *any* substrate it will die and decay. This will result in more ammonia entering your cycle. I know of no other "gas" that decaying Java emits. I planted mine on driftwood. Just cut a sliver, leaving it attached to the wood. Then use this sliver to clip the base of the fern to the wood. That will hold it in place until the roots grab the wood. Don>

Columbian Sharks (Arius seemanni)  9/26/04
Hi There,
<Hi, Pufferpunk here>
I was just on your website and I found a lot of
interesting information about the Columbian Shark.  I
do have a question that I did not find an answer to on
your site.  I just bought two small (2 inches or so)
sharks and I believe they are Columbian sharks.  They
are very silver almost metallic grey and very sleek.
They have very long whiskers and look identical to a
real shark.  
<Have you read this? http://www.wetwebmedia.com/ariidcats.htm)
Now, my question is: why would they be
swimming upside down?  They are not just floating
there in they water but actually swimming quickly at
the top, upside down!?
<Are they upside-down all the time?  Are they gasping for
air?  Or do they straighten out after a while & swim normally?>
Sorry, I actually have one more question in regards
to these sharks... Is it okay to have them in a tank
with goldfish?  I know it sounds funny but They are in
my 40 gallon with a large (8 inches at least) pond
goldfish as well as a 3 inch feeder goldfish and two
2-3 inch fantail goldfish.  They seem to be doing well
with them so far but how long will this be okay?
<Absolutely not!  GFs are Very messy, high waste-producing
cold water fish.  Your "sharks" are actually tropical,
brackish water fish that prefer saltwater as adults.  They
also grow 14-18" & require a huge tank. You never mix tropical
fish with GF.>
If you could please answer this I would greatly appreciate it.
<I suggest either setting up a separate BW tank for them
(expecting to need a very large tank in the future for these
fish), or return them.  ~PP>
Thank You !!  Ashley

More Ariid Cat/"Columbian Shark" compatibility questions
Hi Bob (or other WWM crew member),
    I have yet more questions about what I can keep with my
Hexanematichthys seemanni. I was reading on WWM that some fish look at
cleaner shrimp as a $1.75 snack. Are Hexanematichthys seemanni one of
these fish?
<Too likely yes. Bob Fenner>
Thank You
-Joey

White tipped Shark Catfish/Columbian Sharks?
Hi,
I was just wondering exactly how long these catfish should be kept in freshwater conditions.  Currently our 2 are each an inch and a half long and living in a freshwater tank 75g with small amounts of aquarium salt added for general health.  At what size do we need to slowly adjust them to a saltwater tank?  (How long can we keep our little guys as I do not plan on getting a separate Salt water tank?)
Thanks,
Andy
<Actually, unless the source water is quite hard and alkaline, this species should never be kept in straight freshwater... it's a brackish to marine species. Please see here: http://www.wetwebmedia.com/ariidcats.htm
It can be kept in minimally (spg 1.005) to about full strength (spg 1.010) brackish water for years, but is better off in near seawater (spg 1.025) water when a few to several inches in length. Bob Fenner>

Ariid Cat/"Columbian Shark" compatibility questions
Hi Bob (or other WWM crew member),
    Currently I have two 4-5" Hexanematichthys seemanni In a 30gal
long (36x13), But I will soon be getting them a 180gal All-Glass drilled
tank that I will use to rise the salinity up to 1.025 (over 18 months)
from 1.000. Anyway, I would like to know if they could be kept with a
yellow tang and a clown fish+anemone and other inverts. Thank You -Joey
<Should work out fine. These are really beautiful catfishes, especially when large, in mixed saltwater settings. Bob Fenner>

Breeding Arius seemanni
I have two Arius seemanni (Columbian sharks) in a 55gal tank. Their
tankmates include silver tip tetras, zebra and leopard danios, blue German
rams, mollies, and angelfish. I know that some of the species are not the
best tankmates for various reasons as ph, salinity requirement later in
life (the sharks), and predatory reasons.
<Yes>
However, my sharks are the most
peaceful fish in the entire tank! Everyone gets along wonderfully. Now, I
had originally started out with just one shark, and then I picked up another
a few months later. I know they don't like to be alone. I have another 55gal
that I can setup for them. I was wanting to know how to go about attempting
to breed my sharks. I have raised various other tropicals, but I really
would like to try my hand at this challenge. Any advice would be helpful!
Thanks in advance!
Sincerely,
Theresa
<Interesting quest. I don't know/think this ariid catfish has been spawned in captivity (all are wild-collected as far as I know). A few notes: the genus of this fish has been changed: http://www.fishbase.org/Summary/SpeciesSummary.cfm?ID=13480&genusname=Hexanematichthys&speciesname=seemanni
Adults live in seawater, they are likely mouthbrooders, with the males carrying the eggs, developing young (till their yolk sac is absorbed or perhaps beyond) in his enlarge buccal cavity... females develop "claspers" (protuberances about the ventral area) as a sexual distinguishing feature. Bob Fenner>

Distressed Arius graeffei
Hi guys!!
<Hi there>
I recently added 2 Arius graeffei to my 60"x18"x20" tropical tank society of approx. 25 fish and 14 yabbies.
<Yikes... pretty crowded>
Unfortunately, these fish won't relax.  There was a third fish at the store when I purchased the 2, and was wondering whether the neurotic behaviour of the purchased 2 was due to potential emotional stress due to separation from their friend/family member.
<Not IME... this is just one of the more diurnally active, make that ACTIVE catfishes>
The pair haven't settled down after a couple of weeks, and I was wondering whether this was due to the pair being of the same sex, or because of the absent 3rd Arius graeffei. I have constructed roomy rock caves for habitat in the aquarium for their lair, but still no peace.  Their behaviour distresses the ecosystem, and I can't put up with it for much longer!!
<Maybe time to trade them in>
Please help me with some advice and experienced stories before these two Arius graeffei learn to swim in salt water..
<They may do so... naturally>
Kind regards,
Aaron and Matty T
<Bob Fenner>

Sharks
I'm thinking about getting either a Bala shark or a silver-tipped shark.  I'm
getting a 55 gallon tank and want to which shark would do better in that size
tank,   Can you help me?
<<In the future, can you send your emails with the PROPER PUNCTUATION, please. These emails go directly onto our website, and we prefer it to look a bit more professional. Thank you. Also, what is the scientific name of the silver tipped shark? I will assume you mean the Columbian shark, which will grow to about 6-8 inches. Columbian sharks are carnivorous and can be aggressive. Bala sharks prefer to be kept in groups, and are quite pretty and less headache than most freshwater "sharks". A group of Bala sharks will also grow larger. What species of fish are you planning on keeping with your shark? Either way, be prepared to do regular weekly waterchanges. In my opinion, you may be better off with a red-tailed shark or a rainbow shark. Please do not cycle your new tank with a shark, however. -Gwen>>

Arius seemanni Venom (3/7/04)
Hi, <Steve Allen today>
  I have a aggressive Arius seemanni and I have read that they have
anticoagulant venom. My question is, what would happen if I where to be bitten <the venom is actually through the dorsal spines>, would this pose a risk to my health (could I get sick/die), and
what should I do if she does bite me? <I found little about this on the internet, suggesting there have been few cases of actual harm. You might w ant to do more research on the web or through a university library. Anticoagulant venoms aren't really likely to kill you, but there could be a lot of localized bleeding. If you got a lot of venom in you, it could possibly cause serious problems. In your position, I'd keep my bare skin out of the tank. Get some puncture-resistant aquarium gloves and keep an eye on him. If something happens, cal your doctor immediately. > Thank You-Joey <Hope this helps.>

Columbian Shark Acting Weird 1/13/04
<Hi, Pufferpunk here>
Hello, I am kind of new to this fish stuff but it is fun,  
<Welcome to my passion--fishkeeping!  I hope it will become your passion too.>
I have a 55 gallon tank and 2 small Columbian sharks, and a couple other small fish in the tank with them, I.e. a red tail shark and a couple of small catfish.
<I can already see a problem here.  Columbian Sharks are brackish water fish, that prefer saltwater as adults.>  
But my worries are about  one of the Columbian sharks, its belly is huge and it seems to swim in circles and not ever able to gain any sort of equilibrium and maintain normal patterns like the other Columbian,  All other fish are fine and water is of good quality.  It is like the shark is doing back flips and other acrobatic maneuvers...I am just worried and would hate to see it die or suffer.  
<Is it possible to quarantine this fish?  I think it might have internal parasites.  It is a common thing with wild-caught fish.  If it's eating, try treating it with Discomed, by Aquatronics.   If you can't separate it, all the fish will have to eat the medicated food.>
Thank you so much and I Love your site I have learned a lot.  Dennis Barnard
<You're welcome & keep learning--Pufferpunk>

Arius seemanni (shark catfish) with cloudy eye (10/14/03)
Hello WetWeb crew!  
<Hi! Ananda here today...>
I just had a quick question, I have a pretty good sized Arius seemanni, he's maybe 6 or 7 inches and because the tank is a reef tank and he's a little rough, he gets small scratches and scrapes from time to time, he heals up very quickly, but it looks like he may have scratched his eye recently.  
<Ack. I'm glad he's in a tank with some salt, but scrapes and injuries are going to be par for the course in a reef tank... these guys are shoalers and need some open space to swim around in.>
A day or two ago it started out as a very cloudy, but splotchy looking deal, but now it's uniform throughout his eye but slightly more clear...it is possible he has a disease resulting from the scratch (I ask just because it's changed form slightly) or is it more likely that this is just his healing process?  
<Could be a developing infection. You might consider setting up the quarantine tank for him for a bit and medicating with an antibiotic... on the other hand, since it's likely to be difficult to catch him, you might just observe him for a few days and see what progresses. Do keep the water quality pristine, and wear aquatic gloves when you put your hands in the tank to prevent any of the bacteria on your hands/under your fingernails from getting into the tank. Also feed him high-quality foods, perhaps an antibiotic food if you have one that he will eat.>
His behavior is completely normal otherwise.  
<That's always a good sign.>
I appreciate your expertise!  Thank you SO much for your time!
Rachael Loose
<You're welcome. --Ananda>

Sick Columbian Shark (09/14/03)
<Hi! Ananda here today...>
I just started a new tank, also my first tank.  The pet store that I bought everything from was no help in setting up the tank.  
<Not at all unusual, unfortunately.>
After asking many questions all they said was to add salt to the tank.  Well after about two
weeks I thought things were settling down after a phosphorus bloom, and learning more about keeping a brackish tank then I ever thought I'd need to know.  
<Okay... if you haven't read it yet, hunt up Neale Monks' "Brackish FAQ". A Google search should show several hits; some sites have it in html, others have it in PDF.>
The ph is steady at about 7.1-7.2.
<Hmmm. Kinda low for brackish, but steady is good. What's your source pH, and what's your s.g.?>
The nitrite level is high (5), which I've been told is normal until the nitrogen cycle completes and the biological filtration develops.  
<Ack! But too high for your fish. Do a water change ASAP!>
Also the natural sea salt was added according to the directions.  However after realizing I might need a specific gravity tester, the tank shows almost freshwater results.  I have
been adding salt slowing over the past day to try and bring it up.  I've heard that Columbian sharks like increasing salinity as they get older, so I'm starting fairly low with a 1.006ish specific gravity. (increasing to 1.015 gradually over a year)  
<Sounds good. Just use slightly brackish water for top off, and/or use slightly-more-brackish water for water changes.>
I can't understand the disappearance of the salt that was mixed in at the start.  Could the filter remove it?
<Unlikely. How much salt did you add, or how high a specific gravity did you shoot for at first? Also, what kind of hydrometer are you using? If it's a floating thermometer-hydrometer, it will give you readings that are not accurate for your tank temp -- they're calibrated for 60 degrees F, and you need a chart to convert its reading to get the reading it should be for your tank temp. That's why I'm not fond of those. Well, that, and the fact that they're fragile -- I've broken two of them! For brackish, you either want a SeaTest hydrometer (made by Aquarium Systems) or a refractometer.>
Unfortunately the fish were in the tank through my inexperience and changes to ph, salinity, and chlorine removal. They have all held up very well until about three days ago.  The Columbian Shark sits in his favorite corner, but no longer swims, just lays on the bottom.  His dorsal fin is also tucked back and no longer up like usual.  He perks up just fine when it's feeding time, and seems to eat normally.  But then goes back to laying.  There are
no noticeable marks, scars or growths.  I'm hoping it's just the changes and that he'll be back to normal soon, but better to be sure.  Thank you very much for your time.  -Dan
<It's the nitrite. You could take him out and put him in a quarantine tank, doing daily water changes to keep the ammonia down. Or you could leave him in the main tank and do water changes to keep the nitrites down -- though that would have the unfortunate side effect of lengthening your cycle. I'd go with the quarantine tank -- it doesn't need to be anything fancy; a sturdy plastic container will work. Do check the WWM site for info on quarantining and tank cycling... there are also a few pages about the Columbian sharks. I am very glad you have him in brackish water. And do check out the brackish forum on the WWM chat forums: http://wetwebfotos.com/talk/... --Ananda>

Columbian shark on hunger strike
I have learned so much from this website that I am convinced that I should be paying for a subscription!  Anyway, I have a 2-3 year old Columbian Shark that until recently has lived a very happy and healthy life.  About 2-3 weeks ago I moved about an hour and a half away.  I took my shark with me and setup his new tank.  His old tank was a 35 octagon... way too small! I now have him in a 55 gallon tank alone with a nice big pump to give him plenty of current in the water.  
<With an ultimate size of 14", a bigger tank will be necessary, eventually.>
In the past when things have changed in his tank he refuses to eat for awhile (about 4-10) days.  So after I moved him into his new tank I assumed he wouldn't eat for awhile.  
<Have you been testing for ammonia, nitrite, nitrate, and pH?>
I was right, but unfortunately 2 to 2 1/2 weeks have gone by and as far I know he hasn't touched his food.  He swims right by it, but doesn't even think twice about eating it.  
<What foods have you offered him?>
His swimming has become weaker.  I'm afraid I am going to lose him.  Once in awhile he'll be straight up and down trying to almost dig into the gravel... but no food is there.  What should I do?  I figured hunger would make him give in as it always has... but it seems this time he might not recover.  
<Although it's never a good idea to rely on live foods constantly, you might want to give 'em a shot this once to stimulate him to feed.  Guppies or other livebearers might make an ideal treat (especially if you've got a friend or someone that breeds them so you know they're healthy), or if he's not too big yet, you could try live brine shrimp.  Though brine shrimp have virtually no nutritive value (think of 'em as popcorn), they do stimulate feeding quite well.  Soaking them in garlic will help, too.  You could also try soaking his dry or frozen foods in garlic.>
I was wondering if it was possible that he ate a small rock or something and it's stuck inside of him... making it impossible for him to eat.  
<It is possible that he has some sort of blockage.  In that case, you may want to try some cut earthworms to help pass it.>
ANY help would be great.  Thanks!  Steve
<Best of luck to you and your fish.  -Sabrina>

Arius Seemanni Compatibility
<Hello! Ryan with you>
Hi Guys. Your site is awesome. <Thanks!> I have a compatibility question. I have been told by a guy at a local tropical fish retailer that I could put a couple of Five-fin sharks (or Columbia Sharks what ever you would choose to call them
these days) along with African Cichlids. I have been told and found sites to back this up, that the sharks would be able to protect themselves and do better in pairs than on there own. Is it true that I could put the sharks in with the cichlids? I hope that it is because I think those sharks are very neat to watch. What is your opinion?
<I've tried this.  In a 150, I used to keep 10 assorted Africans, a few pictus cats and a pair of Columbia Sharks, Arius Seemanni.  Everything initially was a success.  After a year or two, the pictus cats started getting tormented.  The Columbians were not far behind.  They did defend themselves quite well, but it was stressful enough that I removed them.  Africans are unpredictable- This may work fine for years, or may be WW3 the second you remove them from quarantine and introduce them.  Does the benefit outweigh the risk?  That's the question you'll have to answer.  Good luck! Ryan>
Cheers.
Mike

Arius catfish - 02/24/03
Hi there!  I Hope everything is well over there!  
<Hi from Ananda today... >
I'm writing about a Silver-tipped shark I have, it's about 5 inches long, in a 55 gallon tank, is this tank too small at this point?  
<For a 5" fish, a 55 gallon tank should be okay for now.>
He isn't really active at all during the day, at night he swims all around with the smaller silver tip I have, the smaller one however swims constantly, mostly near the "lair" they share, but he never stops swimming.  They are both living in a full-saltwater tank, I have heard that as they get older they do best in a brackish to saltwater aquarium and I was just wondering if this is right?  
<I have read/heard this many times.>
I guess I just feel that the larger shark is abnormally lethargic during the day, and I was wondering if it was due to the salt?
<You could try varying the salinity a bit -- if you are at 1.025 now, see what happens when you drop the specific gravity down to about 1.020. I would drop the salinity by using less-salty water for water changes. But go slowly if you have inverts.>
All the other fish act normally, the inverts in the tank are doing great -- the water parameters are ideal, what could be wrong with this guy, if anything? As he's gotten larger he's slowed down a lot, when he was little he was very active, so could it just be part of growing up for him?
<It's possible.>
Any thoughts would be helpful!  
<How much water flow do you have in this tank? If your filtration doesn't have a lot of turnover, I'd consider adding a powerhead or two on one end of the tank, pointing at the other end of the tank. These fish are reported to like current.>
thanks so much, have fun today!
Rachael
<You're welcome. --Ananda>

Randomness (Ariid catfish, brackish maintenance)
Hi again! 
<Hi Rachael!>
Sorry I write you guys all the time, but it's only because you give the most reliable advice around! I have an Arius Seemanni that I've written to you about several times and he's doing good, except that every few days he won't eat, I've tried everything in the store in regards to fresh food, (nothing live lately because it's hard to find feeder-type fish that will survive in a marine aquarium and that aren't in horrible shape like guppies and goldfish.) Anyhow, I have been feeding him raw shrimp and bay scallops for some time now and he used to go crazy over them, now he might eat one piece and then just continue prowling the tank, I have tried frozen krill and he shows absolutely no interest. Every few days he will just gorge himself on food and then the next two days he will just pick at it, is he just full? or is he silently complaining about the food? I know he needs a lot more variety, but I don't have the money to blend up a whole batch of vitamins and plants and fresh meat for one little fish, it would spoil too quickly, so I'm holding out on the big stuff until my tank cycles fully and I add more fish that will help him clean the plate (and clean up the mess he makes). He still readily eats flake food, but I know that's not the best for him so I only use it when I feel helpless.
<Feed less, a little several times a day, only what he will eat in a few minutes. Net whatever he doesn't eat out of the tank, it's contributing to your water quality issues. Try freezing your prepared food blend in ice cube trays and thaw a small portion to feed. It's very common to overfeed fish and spoil water conditions, which then leads to more problems.>
Ok! the next thing! My tank has had a relatively high nitrite level for about a week now, (I would normally assume that that's why the Silver Cat isn't eating, but his boycott of food is intermittent, so I'm not so sure) But how can I get these levels down? The ammonia is undetectable, and the PH is perfect, I know all the FAQs say Nitrobacter can't reproduce well until the ammonia is gone, but is it normal to take a week or more? I'm just worried about the long-term effects it might have on the catfish. I have added some live rock (I'm buying it piece by piece due to my extreme poverty -- that's the life of a student!) in hopes that it will help bring down the nitrites. The LFS said that water changes would be fine but really I have to just let this cycle out...What to do, what to do!
<This indicates your tank is converting ammonia into nitrites. This is very likely contributing to the stress on your fish. You need to do water changes to keep this under control!!! It will "cycle out", but it will reach a level unhealthy or deadly to fish! Also, make sure the rock you add is well cycled.> 
The last thing, I promise! I was reading some of your FAQs and I saw something about salt creep! I was stunned, there is even a name for what I'm seeing! All I ever see is warnings about not "salting-out" your fish, but what about all this salt that is getting away!? First of all, I know it's because of my pump and aerator, but I don't want to remove the aerator because there is really no other source of oxygen in my tank, the skimmer doesn't seem to be doing much in the way of oxygenating, so I didn't really know what to do. I don't like cleaning the salt all the time but if there's no other way then I'll just deal I guess! Sorry this email is so long! Thanks for your patience and help! Sincerely, Rachael
<Remove the aerator, they don't do what you think. They produce slat spray which you see in salt creep.
The skimmer oxygenates just fine. You don't want to see bubbles and they can actually cause problems. Hope this helps and you're doing well in school! Craig>

Arius seemanni
Hello! I have just recently found your site and your faq responses are amazing so I thought of you first when I started having problems with my new 55 gal. tank. 
<thanks kindly>
Right now the tank is cycling, it's about 20 days in and the only fish in the tank are one Black Molly and Two Arius seemanni. 
<an interesting mix... not quite compatible either... these "sharks" grow to nearly 24"!>
The sharks were not originally intended to be in the tank during cycling but I have had them for a year and a half and they have outgrown their tank horribly and the larger one was actually injuring himself when he got excited so I thought moving him up right away was necessary....I think I may have moved too soon. I have been religiously testing the ammonia levels at the LFS and the woman regularly tells me that the ammonia spike is coming and although my levels aren't toxic just yet I should watch the fish carefully and change 20 - 25% water at least once a week. 
<agreed>
Ok so the problem. I have followed her directions and in all actuality ammonia doesn't seem to be the problem. But my largest shark is looking bad... his color has drained to a light silvery splotchy color and over the last few days he has slowed down a lot and is having trouble swimming. He sits on the bottom is awkward positions. His breathing is a bit labored but certainly not the worst I've seen. He also looks to be developing a case of hemorrhagic septicemia, but I suspect that it is not his primary problem but rather something that developed from his weakness. Neither of the other two fish are showing any kind of signs of illness. I can only think of one thing that has changed since I set up the tank. 
<actually... symptoms like this are common in stunted fish and fishes kept in tanks that are too small... it may be the case here. There is no such thing as a "healthy" stunting of a fish in accordance with their tank size.> 
I have been adding salt slowly to bring up the SG, which is now at around 1.011 and this subsequently killed off all of the white cloud I had in the tank 
<very good!>
and my only choice for feeder fish were guppies :( The larger Arius is really the only one that actively takes live food and it's a possibility that he was the only one who ate them could that be why he is the only one who is affected? 
<possibly>
I'm going to treat for the septicemia right away, but I don't want to lose this fish, his friend will be lonely so if you have any ideas on what I have done wrong I would appreciate it :( Sincerely, Rachael
PS Sorry this is so long!
<no worries... and aside from tank size you seem to be well informed and certainly empathetic. Lets treat the fish in a QT tank if possible with a Furan based medication. Best regards, Anthony>