Have you tried adjusting the air bleed
[hr]
per instructions? Open the air bleed until you see a bubble in the intake tube then close the air bleed just until the bubble goes away. Try this a few times to get a feel for the right setting on the air bleed. I know that the Seaclone does not have a good rep, but my experience is that it works just fine, consistently producing a dark concentrated skimmate. You do have to keep the foam filter clean.
A tip on using the Seaclone, or other skimmers, is that using Amquel or other water treatments/stress reducer will stop your skimmer from properly foaming. It can take a week or more for that stuff to work its way out of the tank.