[The Codfather]

I had one temporarily on my tank when i was switching over to a new sump. The problem with these overflows is that it sits too deep in the water. A correction for this would be to get a very thin sheet of acrylic or plastic and block the bottom 3/4 of the overflow off. This make the overflow pull water more from the top end,hopefully also pulling it off the surface giving you a proper skim off the surface. Hope this all makes sense. This is what worked for me in the short time i that i used it. I now use it on my hospital tank. I do have a pic. if you need it, just have a hard time trying to place it on this thread. I have a pic. under my 150 gal. tank in my profile if you wish to see it. I still do not know how to post on this site too well. Hope this works out for you.
Bob