betta fish gasping for air

Question
Thanks for your quick response, but the poor thing died this morning. We live in Germany and were told that the tap water would be safe for fish, and the pet store didn't mention any kind of water treatment. I read a lot about treating the water today (after the fact),but will have to get familiar with the products they sell here. Is it true that distilled water is good for them? Obviously we will check a different store if we decide to get another one. I'm hesitant, though, because I don't want to kill anything. Can you direct me to some good info about starting up again and care of Bettas? Also, do you think ours could have been  saved if we had been able to treat the water immediately? We had nothing at home when I wrote the first mail.  Poor fish. we feel really bad about this.
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-----Question-----
We seem to have a bit of a family emergency on our hands - my daughter's new betta fish (we've had him one week) is laying on the bottom of the bowl since last night , gasping with an open mouth. We changed his water yesterday. His gills are dark red...but have been since purchase (we assumed it was the natural coloring). His fins are also somewhat frayed, but otherwise seemed to be healthy apart from not eating since we got him.  Please advise us as to what we can do for him- we feel so bad that he is suffering  from our lack of knowledge.  Thanks very much.
-----Answer-----
I am sorry your betta is sick.  Let's first start with some basics.  Did you put the chlorine out when you changed the water? Was the water the same tempature as before?
Now on to somethings you can do....  
1. Correct the above if that was a problem.
2. Put an aerator in his bowl if he doesn't have one.
3. Treat him with fungus clear by jungle as that helps a lot of conditions.
Good luck!

Answer
I am not in Germany nor have I ever been there so I won't pretend to know what you have there or anything about your water, what I do know about is bettas!
I say if you try again and I think you should that you SHOULD treat your water!   I also think you should aerator to keep the water moving and they like to play in the bubbles anyway.
The bigger the better.  I know you can buy all kinds of little things to keep bettas in and here in the States anyway they sell them in little containers but they are much happier in a bigger place, wouldn't you be?
Good luck !