Don't ask me how I got this to happen. It's a 20 gallon tank with a standard fluorescent bulb. I did a water change and cleaned up the glass with a razor. The algae was coming in a bit. I added some Excel to try to keep the algae down, and then I saw this.
I can't get my large tank to pearl ever and it's got CF
lighting and Flourish dosing. Eh, go figure... I have video of the pearling too, but YouTube is acting up. I'm sure you can all imagine what bubbles coming from a pile of moss is like.