120 Gallon Progress

[TheReefGeek]

You definately have to find out where the microbubbles are being produced first.

It could be an air leak in the plumbing, from the water draining into the sump, or from the skimmer.

You need to narrow that down first. Testing is pretty easy. First a visual inspection. Is the drain line from the display into the sump making bubbles? If yes, follow them, are they throughout your sump, and going into your return pump? If not, shut off the skimmer for a while and see if the microbubbles quit. If they do, then it is from your skimmer. If neither of these seem to be the problem then likely you have an air leak in your plumbing somewhere.

I wouldn't put a filter sock on anywhere until you narrow down the problem first.