Just remember that a fuge and a sump are two different things. In my experience of running a fuge as part of my sump it never worked 100%. You need slower flow through your fuge to take full benefits from it.
If at all possible separate them from each other. There are several designs out there to look at. On my last build at home I elevated my fuge over the sump and used tees in the plumbing to slow down the flow of water into the fuge while keeping faster flow to the rest of the sump. The water from the fuge then flows back into the sump at the bubble trap.
John
"Critics are men who watch a battle from a high place and then come down and shoot the survivors." Ernest Hemingway