pkins44, how big and fast is the Fox? Jb fly, I was thinking about the Perch part of it. I have a lot more luck with Perch and buggy flies than I do with Walleye. You may want to size down the same things you use for Walleye though if you get into Perch.
I was also thinking about what I said about the conventional tackle wisdom you hear sometimes. Like the bite dies off during Mayfly hatches. Or Fish flies as they call them here. I tie big Hex patterns that get Walleye during those hatches. The bite doesn't die, it just keys on stuff the gear guys don't use.