Question
QUESTION: My fish's tail has curved to a 40 degree angle and it's listless. The rest of the fish are well and active. Any ideas?

ANSWER: Hi Kathy!
It is very little information to go on. You did not say how old the fish is, when this started happening, if he is eating, etc.
From the little bit of information you gave me I am inclined to say it is a genetic defect.

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QUESTION: In JUly I started my pond with 1 golden orf,2 red comets,3 koi and 1 butterfly koi.In september i was given 2 shubunkins.A week later one of the koi died,it had fungus on it.Following advice from where I bought my fish,we regulated the pond water until all nitrites had gone and I have my own testing kit,the water is clear.The shubunkin I am querieing about I have isolated from the other fish to avoid contamination.It has been isolated for a week now.It is listless,doesn't swim around,and its tail is bent.I dont know how old the fish is but imagine it wasn't in the aquarium shop very long.I would guess its less than a year.Should I feed it? I am feeding the other fish very little now.I hope you can help me,I feel awful leaving the fish in a bucket but dont know what else to do!

Answer
Hello again, Kathy!
If the fish is outside and it is cold, then he should not need much food and without a filter it would contaminate the water anyway.
I am sorry to say that there is very little you can do.
You might try adding some kosher salt (NOT regular salt, it has additives poisonous to fish) to make him more comfortable. Also test the water in the bucket for Ammonia and Nitrites.
Maybe put in an oxygenating plant for him to nibble on if he does get hungry.