I plan to purchase a juvie Jag and grow him out in a 75g. Once the fish outgrows the space at around 12-14" I can upgrade. With that said how long before I would need to upgrade or would it realistically be good in this tank permanently? I have read much conflicting stances on this topic some say 75 is min some say 125 is min. Lots of size variation too; some say they get 18" but realistically rarely hit more than the 12-14".