my fish looks sick, i dont know what to do

Question
is it ok to put him in a bowl without a pump/bubbles just for a few days to seperate him from the others or will that be no good because he is use to having one?
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-----Question-----
i have had my fantail fish for about 2 years now and he is now in a tank with a
few other fish but the last few days he has been floating in the one spot most
of the time (he still moves around a little but nowhere near as much as usual)
also, just today, i noticed that his eyes are looking abit cloudy/not normal
and also on the tip of every part of his tail, it appears to be torn. he is older
than the other fish and a bit bigger but im wondering if he is just getting old
or if he is sick or if the other fish are bulliying him or trying to eat him? they
are well fed fish so i dont think this would be the case?
-----Answer-----
Hi Donna,
Your fish seems to have cloudy eye and tail rot. These problems are brought on by poor water quality. Get your water tested for ammonia nitrite and nitrate. I would isolate the fish if you can because cloudy eye is contagious. It seems as you may have a water quality problem which means you need to do daily water changes every day of about 30% to help the fish recover.

Good luck!
Chloe.

Answer
Hi Donna,
It will be okay to put him in a bowl without an air pump although this has to be temporary. Try not to overfeed and you must try and change the water every other day because the bowl is so small it will have lots of waste in such a confined area which will cause high ammonia levels.
Regards,
Chloe.