gas bubble disease

Hi everyone, here I am again asking for help. I noticed today that there are some transparent bubbles on my cardinalfish's left side. The fish was staying most of the time in the corner of the tank ( quits the corner sometimes ) since a few days but I didn't think much of it because it actually...

I have a bubble wand in my aquarium 120g DT/30 gal sump. I just saw a post with a picture of a fish with bubble disease. Am I asking for trouble with my bubble wand. I have a gyre on both ends and my new protein skimmer is still getting turned in and sheds bubbles that end up in the DT. Should...