sick/dying beta?

Question
 I've had my beta Bruce for almost a year now. He lives alone in a very small tank with some colored rocks at the bottom, and I change his water about once a week. There is no filter system in the tank, and I have not checked the water chemistry at all; however, I have not changed anything about the way I handle him since I got him.
  In the last week or so, his behavior has started to be really strange. For a while, he was really aggressive and would flare up if anything came near his tank at all, such as my hand.
  Now, he's almost the opposite; he won't eat, and he's been hovering near the top of the tank, often almost all the way on his side. I've thought he was dead a few times, but then when I move my hand near the tank to get his attention, he swims frantically around the tank for a bit, almost like he's having a seizure, only to return again to his position near the top. I'm very attached to Bruce, and I fear he might be dying. I know betas like to be warm, so I put a lamp near his tank to try to keep him warmer. Do you know what's wrong with him, and is there anything else I can do for him?
  Thanks.
   ~Andrea

Answer
Hi Andrea;

What you might try is feeding him pieces of green peas. If he stays near the top a lot it could indicate he has gas in his belly from constipation. Feed only the peas and no other food until he is better. The peas help things "move along" better, so to speak.

He is getting to be quite an old fella, so he may be getting sick much more easily from now on. Male Bettas are close to a year old when we buy them in stores and their lifespan is 2-3 years. Yours is 2 years old now. Keep him as warm as possible and maybe change his water more often now. This will help his immune system be stronger.

Followups welcome

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Chris Robbins

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