help my goby dragon

My goby dragon was in another tank for almost a year. It was getting attacked by the African Chillid (i think that is how you spell it) so I bought a 3 gallon hex tank to separate him. I used the water from the old tank and new gravel. For the first few days he was fine, hiding behind his rock and behaving as a goby dragon should. Since yesterday (May 1), he has been swimming to the top repeatedly and almost gasping for air. I added a water filter and an air stone to help but he is continuing to do the same thing. He is not eating and there are a ton of bubbles at the top of the tank. Any advice would really help. Thanks, Nancy
PS--I am a novice at this and thought it I was doing a good thing by taking him. I am beginning to think I made a mistake.

I am by no means even an amateur at this yet, but everything I have heard/read says to check the water readings first. Since I did not note any mention of them in your post, thought I would ask.....

All we tested for was ammonia which is at 1ppm. The water is cycling. The fish has been in there for one week.
Thanks. Nancy

Add some gravel and plants or decorations from the established aquarium. That's where the good bacteria live, not in the water. Once the good bacteria are established, they will take care of the toxic ammonia and nitrite. Check some of our blogs to find out more about the nitrogen cycle, and be sure to avoid over feeding.