if u'd like some pointers on improving your pictures the following could be done,
1) No crazy angles like the second shot
2) Wait for the fish to be either directly sideways or facing you before taking your shot, a fish swimming away from you hardly shows off the qualities that make it a good fish.
3) Better focus on the fish, have the fish take up more of the shot so there isn't as much distraction from all the other stuff in the tank. In your second shot the wierd head ornament looks like it's the subject of the shot, not the fish.
It looks like a nice fish, and your pictures aren't blurry or anything, it's just a matter of knowing what to include in your picture that you need to work on.