This question is on behalf of my sister who has tropical fish. She has a 4ft well established tank with relatively few fish in it (approx 10 tetra size fish) but on adding a couple of new fish they seem, in turn, to be developing a hunchbacked or `kinked` body. I`ve looked on the internet but it`s just made me more confused with all the scientific talk. Any ideas as to the cause that can be easily explained?

I had a tetra who was like that, he was like that when I got him but when the guy noticed he gave me 2 extra fish free. It died. I have no idea what was wrong with it though, and the rest were ok.
Not much help, sorry!

x

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one or two of my 4 year old danio`s are like it,i wouldnt worrymaybe its a sign of maturity???

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(formally clare7577)

Why would the fish that were previously ok start to bend though once a bent one was added to the tank? It seems to be something that`s spreading.

Fish suffer from TB which causes spinal deformity, that and the lack of proper nutrition are the two causes of bent fish.

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it does sound like a dietary deficiency of some sort

Aquarium FD - Fish Vitamin Deficiencies - Disease Identification, Diagnosis & Treatment

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This is not a game of 'who the fek are you'.

Not a single gram of fek shall be given today.

one of my 7 week old platty fry has it

One out of how many? are you feeding good quality food that has not been hanging around for ages?

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only 1 of them has it, they are fed tetra min, and occasional blood worm

I would be tempted to euthanise it as it will just suffer, keep an eye on the rest.

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