You guessed it (or not), Bubbles! This is the newest behavior in Blondie's repertoire.
During training sessions, the lumpfish would look up at us while they were waiting for food or the next cool behavior. Sometimes, Blondie pushed water from her mouth right below the surface to make a mini bubble machine. It was so cute, I wanted to show everyone. I put this behavior on a signal by positioning my hand above her head so that she is facing upwards. I give the signal, which is "a starburst of fingers..." (that's a hard one to describe!) with my right hand and wait for her to spit out a little bubble. I immediately reinforce. You can see in the video, she catches on fast- one time she even jumps the gun and blows just as my hand gets into position! This is a great example of capturing a behavior; she blows the bubbles on her own, I put a signal to it.