your fish sounds healthy, iv'e only see mine take a movement <waste eliminating> once, its not particurally the best thing to see, but they usually don't swim to the front, and poo. lol. they just go when they gotta go, good luck.
mines hangs around the top also, and then dives back down, its just a fish thing, his fina are normally down whilt he swims, i used to think there was something wrong with him but he's just find, he tends to nom his tail but other than that hes fine lol.