betta fish digestion

Question
I just got a new male betta fish a few days ago. It is my first fish, and the
only fish in the tank.  My tank holds about 2 gallons of water, and has been
set up for 3 days.  I'm afraid I don't know the pH, ammonia, and nitrite levels
of water in my tank, I hope you can still answer my question with out that
informartion!
       I gave it a piece of flake food on the first couple days-(one flake each
day), which I thought it digested;  but then I found it all at
the bottom of the tank.  I decided to not give it any food for 24 hours, so it
could clear its intestines.  I just gave my fish a flake of food.  It attempted to
eat it, and I thought it digested some of it, but a moment later it spit it back
out again.  I gave it one last piece, but the same thing occured.  I'm not sure
if it just doesn't like the food, or has some other problem I don't know of.
    I was also wondering how much food I should be giving it.  An information
sheet I got when I purchased the fish says I should feed it as much as my
male betta can eat in 2-3 minutes twice every day.  The container I got my
fish in says a few flakes 3-4 times a week.  If you have any idea which piece
of information I should follow, or even a new idea; I'd be happy to hear it!   
 Looking forward to hearing some advice!  --Natalie

Answer
Hi Natalie;

It's okay that you don't have the water parameters. Most people don't test the water in really small tanks since the water is changed so often.

If there is still leftover food on the bottom, clean the tank out. Rotting food can be deadly to bettas because it poisons the water. Normally it needs to be cleaned once a week unless something weird like that happens to need an extra cleaning.

Feeding instructions are often confusing. Bettas' stomachs are about the size of their eye. Feed only a few small flakes or 4 pellets once every day.

Since he isn't eating very well, he may not like the food or his water temperature is too low. Bettas are tropical fish that need to have their water at 76f or higher all the time. If it's too cool they lose their appetite. Unless there is a heater on the tank or the tank lights make it warmer, the tank temp will be the same as your room temp. If it's colder than 76, put him in a warmer spot or put a desk lamp close to help the temperature rise slowly and keep it there.

Here is a good web site about bettas and their care. Click on the links to the left sidebar on the page;

http://www.bettatalk.com/betta_care.htm

At Your Service;
Chris Robbins