I lean towards you jag being a male...i have noticed that tank temp affects their color as well...i had did a water change the other day and saw my jag lighten up... was wondering what was going on until i noticed that i did not plug the heater back in...80-82 degrees fahrenheit he seems to be his best color...right now if you have a 20 cm salvini then your jag is more at risk...be careful...