siamese fighter

Question
QUESTION: Please help my Siamese Fighting fish is looking sick.  He mostly just lies at the bottom of the tank and flaps a bit, although he comes up when I feed him but only for a few seconds before going back down to rest.  I heard that can live only a year or two, and that the more fancy tail they have, the shorter their life.  My fish is just over a year old and he has a very big, fancy tail.  We keep him in a tank that is at the recommended temperature and the water is fine.  We feed him fish food and bloodworms.  He doesn't have any other symptoms but I am really worried about him.  He never acted like this before.  Do you think he is sick or is he just getting old?

ANSWER: Its hard to tell, but I think he is sick and he could be a bit old too. Usually when you buy them in the pet shops, they are around 6 months to one year old. They can live to 3 years if given the right environment.

Tell me what size tank you have and if you have a filter, etc. Once I know this information I will be able to answer the question a bit more easier.

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QUESTION: I think its a 35 litre tank (does that sound right) and yes it does have a filter that was reccomended by the fish experts at the shop

Answer
Keep the filter on very low because they can die from exhaustion. They can't swim a lot because of all of the drag that their large fins have on them. They like to rest and do enjoy getting up and swimming around occasionally. how many cm is your tank? (height, width, length)