betta gills

Question
i just bought a betta fish 3 days ago and it is at the surface of the water and it just stays at one place it does not move around unless i put my hand over it or nock on the aquarium. i have notice that its gills are swollen and its kind of gasping for air at the surface and it doesn't eat(i feed it Bettamin, tropical medley). i have it in a ten gallon tank. i have also added a drop of medicine called: "Quick cure, fast relief for ick and protozoan parasites" i don't know if this will help it. The temperature is 72-73F.
I'm new in fish keeping so am not really good at treating disease on fish.
thanks for your answer.

Answer
Martin,

 There are a few problems. Your Betta is cold. He is a tropical fish and needs his water to be between 80 and 82 degrees. Never knock on an aquarium. It is very loud to them and they will stress if done often. What are his water readings. If he is hanging out at the top, 1. he isn't getting enough oxygen and 2. there is too much ammonia in his water. A rule of fin is never treat your fish with any medication unless you know what is wrong. If he doesn't have Ich, do not treat him for it. I would suggest getting a water tester. Never get the strip because they are not accurate. Get the liquid testers. I would immediately do a 50% water change to help remove the ammonia. Make sure you always use a water conditioner to his tap water. It needs to remove chlorine and other bad things from the water.Check the water everyday. If there is still ammonia or nitrites in the water, do a 25% water change daily until the ammonia is gone. Even if you have a filter in the tank, you have to do 25% water changes weekly.I think after the water change, and the heater, you will see an improvement in him. If after you do that he doesn't get better, or he gets worse, let me know right away.