Hey guys, has anyone heard of a fish called "Karkass"; i'm not sure whether the spelling is right or not, but the salesman at the LFS told me that the name is pronounced "car-cass", they r like discus but neither round like discus nor tall like angels, i think this is a cousin of discus or angel; this fish is silver with large black spots, they grow up to 6"!
Maybe a Spotted Silver Dollar, Metynnis lippincottianus. That is the only thing I know of similar to the description you gave and gets about 5-6 inches.
Yeah strange fish, i couldn't find anything either; the closest thing it can be is a spoted silver dollar may be! or may be it is a new species bred in our country!