They are very adaptable, that’s probably why you’re seeing so many numbers. Too low is way better than too high, so start them off in less light if yo are unsure of what they were kept at. I had one in a tank under a frag rack for 8 months getting about 120 PAR maybe less and it did fine - just didn’t grow very fast. The less PAR the bigger they will try to expand to get more light. I’d say shoot for 200 with moderate flow (enough to move around without seeing skeleton).