To elaborate IMHO the smaller one is definitely a female ..The larger one also looks female( but not out of the realm of possibility for it to be a male)...here is my male at under 5 inches to judge for yourself... Young males begin to develop a more maze like pattern that intensifies as it matures...
You obviously seem to want a pair so for your sake I hope that you do have a male... I had questions about mine at times because he had a very round dorsal fin when he was at that size ... Good luck to you
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