Psirex, I've gone back a little in this thread but may not have seen all, so bear with me as I ask you a few questions.
1. Did you ever have it working correctly??
The skimmer works, I just can't put the gate valve mod on it - even at the lowest level of the riser it will overflow with the gate valve attached. I can attach the mod without the riser but not sure if that is efficient or not.
2. When did you do the mesh mod and can you get a pic of it?
It was overflowing before I did the mesh mod
3. Have you cleaned the venturi?
The skimmer was\is clean of any blockage or build up, it was cleaned before I got it and I thoroughly inspected it before putting it in my sump...
I ask because there seems to be too much water being thrown into the skimmer body. I kinda get the same thing if something is blocking the venturi, like a build up of calcium deposits where the water and air meet.
I will look at the ventri again and replace the tube...
I've done everything except the recirculating mod. I did come up with a different mod to supply water to the skimmer though. I'll get you some pics of that when I get home. Since I just had to replace the impeller, my mesh mod is no longer there. I also removed the gate valve mod because there wasn't room when I added my fuge.