my betta is sick:(

Question
Hi,
Ok so my beta started acting strange a few days ago...I have had it a little over a yr( my friend gave it to me).when  I see it come up for air(as hard as it seems to be for it) It acts like Its hungry but either isn't strong enough to eat or just can't see it??( I have guessed maybe it was blind or something?) But it just lays there at the bottom of the tank and can't swim for long...it tries but jus sinks again. I change its water on a reg. Basis but I dnt have a heater and its in one of those large "vases" betas are sometimes seen in.I feed it Bettamint altho true it has NEVER acted like this as long as I've had it..always acted normal...it looks the same physically.. I always think I'm gonna check on it and it will be dead:( I really hope its ok...! Please give me some good news! I love my betta!!

 Thanks,
  Shayla

Answer
Shayla,
Sorry to hear your Betta is not feeling well. Unfortunately, Betta's should not be in vases. He should be in a tank with a heater. Remember, he is a tropical fish and needs his water to be at 80 degrees at all times. When their water gets too cold they become lethargic. They won't swim or eat. When this happens they become sick and it is hard to get them back. Also, your Betta is getting older and really needs the heater now. Once you get him the right type of tank and add a heater, you should see a big difference in him.