Ok so I tried out the filter sock. Its still spitting out micro bubbles. Not quite sure why. Its not as bad as it was, but they are still flowing through. Its a 300 micron mesh media bag. Also, I was wondering if the Accela pump might be too powerful for the bak pak, I know its the "newest" and "best pump" available made specifically for the bak pak, but I swear, to me it looks like it is pushing so much that it is forcing a good amount of bubbles over to the second chamber, up and out. Anyone here do any easy mods on this skimmer to fix this?