Some ideas,
-Make sure skimmers output is placed at the furthest possible from your main systems pump intake.
And if your in moddin mode
-Tee the output at your desired water line within the skimmer(keep the top vented) and direct this back to the first chamber/s of the sump.
You may have to lift the skimmer a little to get them over baffle hieghts to do this...not too much, the skimmers own pump may have to be lowered to accomodate.
Even better directed back into a micron sock.
-direct the main systems pump intake to a portion of the sump that has the least bubbles.
If an external pump, this needs to be some internal sump plumbing from the bulkhead in.
No need to glue these, just dry fit them and try them out until they work.
- Make sure where the strainer is on the pump intake that the water isnt whirlpooling there on the surface.