The cloudiness should settle with time, the flourite will make it cloudy for longer than usual (I have it in my puffers tank and also in my 39g). I'm not sure if anyone mentioned this or not, but the puffers are super sensitive to nitrates and ammonia, so I would let the tank cycle with the snails for a couple weeks until the ammonia/nitrate levels drop off. Also, I've never known puffers to be sexed. I've always read/heard that they're almost impossible to tell apart just by looking at them.
They sure are fun fish though!! I love ours, they have so much personality, it's crazy, I've never had a fish with so much personality and character before!