Does this look like he's trying to make a bubblenest? I've never seen him at work, but these bubbles are around the top of the plants near the filter, as well as around the filter intake tube and kind of clustered up at the aquarium wall opposite the filter where they've been blown by the current. Because the bubbles are sort of all over the place, I'm not sure if he's trying to build a nest or not, or if the water is bubbling a lot from the filter or maybe the water conditioner or something. I switched to API Stress Coat when he tore his fins. Before that it was Tetra AquaSafe.