Beta problems

Question
Hi Karen,
You've helped me already, I've been reading some of the questions and answers about betas.
My daughter's at college, mom's taking care of the fish - his name is Fish.
I thought I'd give him a treat and used bottled water (plastic gallon container) in a change about a month ago. He went downhill from there. His belly swelled, his scales began the pine cone affect, then he wouldn't eat.
So, I started changing water every 3-4 days, letting the new sit for a day, let him go 2 days with no food, then have been feeding him peas (he loves it) for the last three days. Today when I came home from work, I was thrilled. His belly has gone down considerably, but there is a very small patch of white/gray behind his right fin. It's hard to see. I don't know if a couple of scales are missing or if there's anything on his scales. What do you think?
Also, how do I make him warmer. This beta is used to cooler temps - 60-72 - since we got him about a year and a half ago. But you mention warmth when they don't feel well. What's the simplest and least expensive way to do it?
Thank you for your any help.
Rae  

Answer
Hi Rae,
The change of water with the new bottled water likely was what had stressed the little fella out. I'm glad to hear he is doing better however! The patch of white/gray behind his right fin could be a scrape or injury or it could possibly be the beginnings of fungus infection. Now I'm not saying that's what your betta has but its just a possibility. If the patch seems to be spreading or looks fuzzy, it could be fungus. You can also look here for more help-

http://www.fishjunkies.com/Diseases/columnaris.php

It's always difficult to make a small container warm consistently for fish but there are some ways. The first is to put your betta in the warmest room in the house. The ideal temperature for bettas is about 78-80F. The next way you could try is to position a lamp over your betta's bowl. But you must be careful to not overheat him. Keep a close watch on the temperature. The only drawbacks to this is you have to keep the lamp on all the time but it doesn't really hurt.

Really the best way to keep a betta warm is to get him a small aquarium of 2-5 gallons and put in a suitable small heater which is the best way to keep him consistently and reliably warm....

I really hope this helps!
Best wishes,
Karen~