Hello tetra experts, i'd like to know whether my congos are male of female. Right now they are about 2 inches long, and their dorsal fin seems to be developing some white tips, as well as some while/black streaks in their caudal fin. At first I thought they were males when I purchased them, but they seemed lacking in coloration even in my fully planted tank which is making me unsure. They also sometimes chase each other which makes it even more confusing. Please see pics. Thanks guys