Lol. I go by pelvic fins, same as what you said but relative to analfin. If tips of pelvic fins are long and extend beyond the start of the analfin, it should be male. If pelvic fins are shorter and only just barely reach the start of the analfin, probably female. So same conclusions as you!coralbandit said:I go by analfin. A males may extend into the tale while most females analfin ends at the base of tail.