The hose brackets were a tight fit just for the tank lip, they have loosened some but not enough to expand 3 inches no way there . You could connect to the pvc the ribbed hose that comes with the fx6 only has one end with the rubber piece permanently attached to it so you would need to glue the other end or use vinyl hose, its just under a 1" iner diameter.
You could connect to the over flow and bulk head however that will affect your flow rate not sure how much or if enough to impair any flow.
You could connect to the over flow and bulk head however that will affect your flow rate not sure how much or if enough to impair any flow.