I do have a standard Wet/Dry sump. If I had the room to build one like that above, I would be happy as a pig in s---. Unfortunatly I dont, so I will try to add the return over the balls. My only concern then is that there will be too much water flow over them and will therefore reduce their effectiveness.
The bubbles should go away though.
You all have been very helpful in your replies. Thanks.
Do you have any suggestions for a quiet external pump? I was thinking about an Iwaki 30RLT. 510GPH