I got a 55 gallon goldfish pond in June. It came with three very large goldfish, about 8 inches each. I added four very small goldfish about 2 inches each. I then read more about them and found that they will need a much larger pond. I am in the process of finding someone to make a larger pond, but I am having some problems with the fish now. I have three large goldfish, I am not sure what kind, but they have very large single tails. They are doing just fine. I also have two small black fantail fish. They are also doing fine. I also have two small orange fantail fish. They were fine for the first week, but now they are moving very slowly and keep coming to the surface and gulping air. They are all eating plenty, I feed them flake fool, lettuce and peas. I have a fountain for aeration. I am afraid they will die! They are active during feeding time, and none of the fish are fighting. They don't appear to be injured. But they just float along with the currant most of the time. What am I doing wrong, besides the obviously too small pond? Please help!