NICE TANK!
I just got my Cowfish about 3 weeks ago and I love it. Mine just learned how to shoot/spit water out of the tank at me! He will come up and stick his horns out of the water (sometimes one of his eyes also to look at me) and I will gently blow onto his horns while they are out and he hill lean back and blow water at me!
Once he gets big, he will probably be spitting streams out, lol...
He is also making my clowns braver. They have been watching him eat out of my hand and they are starting to come up there, nibble and RUN!