Title says it all, mostly.

I've managed to get the 2000 prestige, I have lots of tanks filled with various species, decor. Everything seems to go well, apart from a couple of tight spots here and there. Visitors needs are met also. I have podium and lectures for my biggest tanks. But for some reason, I can't get over 50~ guests. Tried adding a few pathway arrow to push visitor to more remote area, didn't seems to help.

What am I missing ?

Beware you can get negative points for too much frequency if you don't change th talk topic. Keep an eye on that; I just ran into that on that same level. I've had the people, but can't break 1800 points yet.