or cyano, judging by the pinkness around the sand(yikes!) did this start with the new lights??
Might just be your anaerobic bacteria at work
I vote anaerobic bacteria. aka nitrogen bubbles.
Do I punch a chad now?
Stop feeding the tank beans..... LOL
Actually I see bubbles coming from my DSB every evening, they do not get trapped like that so yeah you may have a little something growing and trapping the bubbles.