any one with this camera and know how to take good pictures with it?


Ah, dpreview, the last message board I frequented before I got my tank. I have the Nikon D70. HP cameras aren't regarded very highly. That particular model, if I'm not mistaken, does not have manual focus, so when you use auto focus it will focus on the glass. That's one problem. Then there's the fact that it will automatically set the shutter speed according to how much light it needs, so if it sets it too slow, even if it's 1/30th of a second, that's too slow to freeze your fish if it's moving.
If you really want to take good closeups of your fish you'll need either a DSLR or one of those cameras that LOOKS like a DSLR and allows you to control the settings manually.
Update: I see that your camera does have manual settings. Try using those for focusing and see if that helps.