D.I.E.D., one thing I noticed when I first used my AguaVu...when you first start viewing the montitor, it's pretty tough to tell how far out, distance-wise, that you can see. I found that zoning in on stationary objects just didn't give me a warm/fuzzy that I would actually be able to see a fish with in the field of view.
But be patient. When a fish does show up, it'll be real obvious, and more detailed then you might have first imagined.