I have a Waterbox cube 10. I'm currently running a little refugium in the middle chamber, and I just ordered some mud and critters from indo-pacific sea farms to add biodiversity to the tank/help stabilize it. Ideally, I want to put the mud and sand in the bottom of the refugium, but I don't know what it will do to the return pump or the flow between the chambers. Before I do it, I'd love to get opinions!