black bubbels

[proff1949]

Recently moved a piece of coral around and found a3/8 in shiny bubble right next to a young feather duster. Not sure what it is. Any ideas?

 

[spiketooth]

Could you post a picture

 

[Spongeandgary]

did it come from the substrate? One possibility is that its a Hydrogen sulfide gas bubble. Its a by-product of anaerobic bacteria consuming organic material.

 

[Beengirl]

Could be bubble algae, especially if it was near a coral. Google that and see if that's what you have. They're a dark green, almost black color sometimes.