beta fish sinking

Question
I know my beta has swim bladder and have got him through 3 episodes. I fasted for 3 days and then for 3 days did the peas. He does not look constipated but hasn't pooped in weeks. He is struggling straight up to the top to get air then he just sinks, tail first. He has been like this a few weeks. Water is changed every 5 days with same temperature and I have always used tap water dechlorinator. The temp of the water always match. "Do you think the Dahnia will help?"
Please give me any advice possible.

Look foward to hear from you,
Gay Boise

Answer
Hello,
You didn't mention the size of his tank, or the water temperature.  Bettas are tropical fish, and need warm water.  If his water is under 78 degrees, he is cold, and will be hard to cure.  If you raise the temperature, do this very very slowly, one degree every two days, as raising the temperature too fast could be deadly.  He will need an antibiotic.  Kanamycin is very good for swim bladder disease, but sometimes hard to fine.  If you cannot find it, buy Furan 2, or Tetracycline.  Follow the directions on the package.
A betta's diet should be varied.  Betta pellets one day, Betta flakes the next, Daphnia the next, and bloodworms the next.  He must have one cooked frozen pea a week with the first layer removed.  On the day you give him the pea, give him nothing else to eat.  He should have small meals..example 2 pellets for one meal, and he should be fed, twice a day, or three times depending on the hours you feed him.  
Right now you could feed him daphnia, but he needs antibiotics too.
I hope the little man pulls through.  If you have anymore questions, do not hesitate to write me.
Lynda