Hi all, first time visitor. My fiance and I have a trio of these beautiful fish, and one has developed a "twitch" recently. All of the other fish in the tank are fine, and he is 90% of the time, but once in a while, he'll be swimming, and just twitch. Best way I can describe it, is imagine a fish on dry land flopping, and that's what he does, but while he's swimming, and only once at a time, not like a continuous seizure or anything. We haven't changed food or anyhing recently, although we did upgrade him to a bigger tank about a week before this was noticed. I'm just curious as to whether this is somethign to be concerned. Also, we did take a sample of the water to a fish store, and they tested the water, pronouncing it just wonderful for those guys. Any help would be greatly appreciated in setting the fiance's mind at ease.
Possible sick black finned/silver-tipped/columbian shark?
- Thread starter yodafett
- Start date
A few more details. These 3 are all under 4" and share a 20 Gal. with a Spotted Raphael, a Red-tial Black shark, and a rubber-lipped plecostamus, fed a mixed diet of flakes, bloodworms, algae tablets and bottom feeder (catfish) pellets. (obviously not all at once)
Again, and help or adivce would be greatly appreciated!
Again, and help or adivce would be greatly appreciated!
I'm just throwing out a guess, have you ever seen or heard it run into the sides of the tank? Are they skittish at all?
Also, have you checked out the species profile on these guys?? Hope you plan on a big upgrade in the near future
!! The max size from this site says 18"... Heres the rest of the info.
Black-Fin Shark
AKA: Shark Catfish or Colombian Shark
Arius seemanni (Gunther, 1864)
Temperment Sociability Min. Tank Availability Area
Peaceful Groups 90 gallons Common Bottom
Black-Fin Shark Catfish are among the most desirable of all aquarium fishes. They are big, powerful looking animals with sleek silver bodies and active natures. Although distinctly predatory, they are not aggressive and on the contrary, can be bullied by fishes like cichlids. Arius seemanni, sometimes incorrectly referred to as Arius jordani, lives in fresh and brackish waters, and sometimes enters the sea. In aquaria hard, alkaline water is critical, as is a powerful filter and good oxygenation. A specific gravity of 1.005 to 1.015 is about right, with regular fluctuations within this range being beneficial to health. They need a big, roomy tank with a powerful motorised filter.
Some Black-Fin Sharks have been bred in captivity, but not this species. This is presumably because of some missing trigger, but what that is is not known. Females are noticeably stockier and develop swollen pelvic fins when mature. Many Arius species mate in summertime at sea, and being a mouthbrooder the male carries the few large eggs until they hatch, depositing the young fish in rivers.
Black-Fin Sharks appreciate a dark aquarium with a definite current. Decorate the tank with a thin layer of sand or gravel for burrowing in, with large rounded boulders to make caves and lairs. Keep in schools of three or more. Small specimens are adaptable, but above 12 cms (4 inches) they become distinctly restless, perhaps feeling some migratory drive. Fluctuations in salinity and strong water turnover are essential at this stage to settle the fishes down. Compared with other catfishes, these fish are not nocturnal and swim constantly, often into a part of the tank with a steady flow.
Shark catfishes are so named because of their powerful, sleek shape. They swim gracefully, something not easily appreciated in a small tank. Arius seemani has venom glands in the base of the dorsal fins, and should therefore be handled with care. Arius seemanni also possess glands in the mouth capable of secreting anticoagulants, which they use when hunting. More obvious to the aquarist are the continual drumming noises they make. These are possibly used for echolocation and for communication between fishes in the school.
Also, have you checked out the species profile on these guys?? Hope you plan on a big upgrade in the near future
!! The max size from this site says 18"... Heres the rest of the info.Black-Fin Shark
AKA: Shark Catfish or Colombian Shark
Arius seemanni (Gunther, 1864)
Temperment Sociability Min. Tank Availability Area
Peaceful Groups 90 gallons Common Bottom
Black-Fin Shark Catfish are among the most desirable of all aquarium fishes. They are big, powerful looking animals with sleek silver bodies and active natures. Although distinctly predatory, they are not aggressive and on the contrary, can be bullied by fishes like cichlids. Arius seemanni, sometimes incorrectly referred to as Arius jordani, lives in fresh and brackish waters, and sometimes enters the sea. In aquaria hard, alkaline water is critical, as is a powerful filter and good oxygenation. A specific gravity of 1.005 to 1.015 is about right, with regular fluctuations within this range being beneficial to health. They need a big, roomy tank with a powerful motorised filter.
Some Black-Fin Sharks have been bred in captivity, but not this species. This is presumably because of some missing trigger, but what that is is not known. Females are noticeably stockier and develop swollen pelvic fins when mature. Many Arius species mate in summertime at sea, and being a mouthbrooder the male carries the few large eggs until they hatch, depositing the young fish in rivers.
Black-Fin Sharks appreciate a dark aquarium with a definite current. Decorate the tank with a thin layer of sand or gravel for burrowing in, with large rounded boulders to make caves and lairs. Keep in schools of three or more. Small specimens are adaptable, but above 12 cms (4 inches) they become distinctly restless, perhaps feeling some migratory drive. Fluctuations in salinity and strong water turnover are essential at this stage to settle the fishes down. Compared with other catfishes, these fish are not nocturnal and swim constantly, often into a part of the tank with a steady flow.
Shark catfishes are so named because of their powerful, sleek shape. They swim gracefully, something not easily appreciated in a small tank. Arius seemani has venom glands in the base of the dorsal fins, and should therefore be handled with care. Arius seemanni also possess glands in the mouth capable of secreting anticoagulants, which they use when hunting. More obvious to the aquarist are the continual drumming noises they make. These are possibly used for echolocation and for communication between fishes in the school.
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they are slightly skittish, in that if something comes right up to the glass in front of them, they'll shy away, but no, he hasn't been disoriented or anything so that he runs into things. he seems to like the glass an is often right up against it or swimming along with is ventral side against it.