I think it could be swimbladder disease. That is caused by overfeeding as the main cause. It looks like your fish is in a fish bowl and I was unable to determine what the type of fish it was. Most fish other than goldfish are Tropical Fish and need to have a cycled tank with heat and filtration in their tanks. If you have a Tropical fish in an uncycled tank, he could also be suffering from Ammonia poisoning. There is an article you need to read here:
It is probably a combination of poor water qualtiy due to Ammonia buildup and cold water due to no heater and no filtration. It may be too late to save him if he is not able to swim and eat, which it looks like he would have a very hard time doing and if this has goine on for 2 weeks he is very sick indeed. If he has been overfed, he is probably constipated and may even be impacted to the point of not being able to pass anything. If he has totally stopped eating there is not much you can do except maybe get some EPSOM salts at the drug store. Don't get any other kind, it has to be epsom salts as they may be able to be a laxative for fish if anything will help. This is also something that won't cost you a great deal. Put a teaspoon in a gallon of water and dissolve it well. Then very carefully put the fish into the container and allow it to stay in the solution for a continuous period of time with water changes carried out with saltwater of the same type. It may also help to lower the depth of the water to about 5 inches so there is not that much water beneath the fish. For some reason, if the fish is a gold fish raising the temperature of the water by about 5 degrees will sometimes help but you CANNOT do this in a goldfish bowl. You need to get a bucket (new) and put at least 2.5 gallons of water in it and get a good aquarium heater (25 watt) and heat the water to 5 degrees warmer than the room temperature slowly with the fish already in the water.
I also need to tell you that in spite of treatment the recovery rate for this particular condition is not great. Fish may improve for a time, but the improvement is ofter not permanent and the fish will relapse and become worse and die.
Goldfish are particularly susceptible to this condition.
I am so sorry I could not be more encouraging, but it is my feelings it is better to be honest from the start and not build up false hopes then if things go well, we can be pleasantly surprised. But my references, do indicate the above infromation and I will not lie to you.
Welcome to Fishlore.com. The people here really do try to help and are the most friendly people I have ever met. It is nice to have somewhere to come to to find out when you have a problem with your fish or when you need to just take it easy and quit worrying. I am so happy to have met you, I do hope we meet again under better circumstances.
Thank you very much for you prompt answers. Here are more details about my fish.
I'm from Macedonia, Europe. My fish is some kind of carp (locally called karas). It is only fish that salesman told me that doesn't need heat and filtration. I'm sending better picture of fish so you may recognize it. I don't know it's Latin or exact English name.
The fish has appetite, and can swim, but when it's resting it's "floating", it can't stand on bottom without swimming.
He/she said the fish is a CARP. The fish definately is a Goldfish which is basically the domestic relative of the Carp. The short, round-bodied varieties of Goldfish are especially prone to swim bladder disease, which basically means their flotation device goes out of whack and so they can no longer control whether they swim up or down.
While Goldies do not need heating they absolutely do need filtration, just like any fish. They also need a large tank (20 gallons for one). In an unfiltered bowl the buildup of ammonia and nitrite, which bacteria growing in the filter would convert into much less harmful nitrate, is probably making the problem worse. A big cause of swim bladder disease is overfeeding. I have heard it recommended to not feed the fish for a few days and see if the condition improves. Why don't you try this? Don't worry, you are not going to harm your fish--they can go a few weeks without food if they need to. And of course it is not cruel since it is for his own good.
The fact that he can swim and eat is a good thing. However, his chances of recovery are much less in a bowl. If you could get him a tank with a filter he would love you. One question, what and how much are you feeding? Also, how often do you do water changes and how much do you change?
Thanks for info. I have stopped feeding fish for several days, and now she is still with her stomach up, but she is not on surface now, she is staying on bottom of the tank. I'm changing watter every day.
I have found article on internet http://www.netpets.com/fish/reference/freshref/swimbldr.html, where author suggests periodic aspiration of the swim bladder. Can I do that myself?
This means to take a hypodermic syringe and take some of the air out of the swimbladder. I do not believe I would do this. It may be okay for a vet to do this but it would take someone who really knows fish anatomy and has a very clean area to work on. (The fish is not going to lay still while you have him laying on the table waiting to be stuck with a needle) I am so sorry but NO I do not believe you could do it.
Are you changing all the water everyday? It really needs to be in a larger body of water, another tank or a large bucket would do for now with a filter.
Reading these articles will give you an idea of how to take better care of your fish.
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