i think my betta fish may be sick

Question
I have had one small betta fish for about one month.  I bought him at walmart and i also bought a tank that was specially designed for betta's.  I feed him betamin food twice a day and clean his tank once a week or more depending on what's needed.  Now when I first got him he happily swam around constantly....now i find him resting near the bottom of the tank quite often.  I don't think he has any fungus on him because i can't see it, his scales aren't falling off and he may be fading ((but i'm not entirely sure if he is or if i'm being paranoid)).  Other than that he eats normally.  I have heard many different versions on what temperature the water should be, he is kept in my bedroom which is relatively cold but if i move him out of my bedroom one of the small children in the house may stick foreign objects in the tank and kill him.  My main concern, however, is him resting on the bottom of the tank so often.  Any suggestions?

Answer
Hi Aimee;

If he struggles to get to the top, he has a swim bladder problem. If he just rests there he may be too cold. His temperature must be 76f or higher all the time. Put a desk lamp on his tank to give off heat. Watch to be sure it doesn't get too hot or cause a fire danger. There are also small heaters available to use. Check at your local fish store to see what they have and if your tank is big enough for one to be used safely.

Here is info about swim bladder disease too;

http://www.petfish.net/articles/Bettas/swimbladder_betta.php

I hope he feels better soon.....

At Your Service;
Chris Robbins