He's about 3 1/2 inches. His bottom two fangs are coming in and he's starting to turn blue. I'm so happy bc when I first got this fish I posted it up to ask the sex and at the time he looked like a female lol
You'll know when there more spots above the lateral line and spots on the dorsal n anal fins come out. I have a pair in a 240 and they paired up at 4", 3 yrs ago. My males coloration got stronger and more pronounced as he got bigger. Just by looks, you're looking at a male. To be 100% sure, vent it. Good looking little guy. He'll kill that Oscar in 3-4 months,