fancy goldfish is sick!

Question
Hi,
My goldfish has been floating upside down on the surface of the water for the past 2 weeks. (he is in a 20 gallon tank with another fancy and a black Moore) I currently have 3 filters going, (2- 20's and 1 - 30's) I changed a bucket of water everyday ( about 1 gallon), but still it is not helping.
I took him out last night and put him in a bucket because I wanted to relieve some water pressure (I read it somewhere online) I tried feeding him (peas last night and then the anti-bacterial medicated pallets this morning), but he eventually spit out everything, it almost look like something is stuck inside his belly, and he hasn't pooped at all!
Help!!!!

Thank you so much!

Answer
Emily,

  Your fish has swim bladder. I would fast him for 3 days then try feeding him the pea again. After that then fast him again for 2 days days. If he isn't better, repeat the process. Your tank is too small for the 3 fish that are in are in it. Fancy goldfish need a lot of room and so I say put the 3 of them in a minimum  55 gallon tank. Anything smaller is just not appropriate for them. Goldfish do not have a stomach so what they eat comes right back out. They produce a lot of ammonia so weekly water changes are a must. Don't forget to add anti chlorine to the new water before adding it to the tank. I would also feed your fish sinking pellets instead of floating food. When they go to get the food, they will inadvertently grab air as well. I hope this helps.