Is this Pearling?

[enchanted]

I'm posting this in mutliple forums, so I apologize if you see it twice. I know this isn't eggs and are definitely bubbles, but I have never seen pearling. :?

 

[konrad05]

yep that's pearling alright, unless you just did water change...

 

[enchanted]

Nope, no water change in over 48 hours. Cool. Means my DIY CO2 is working.