Interesting - don't have your answer but found this one also:
https://en.wikivet.net/Gas_Bubble_Diseasecan be caused by severe algae bloom also ?
On Wednesday this week it got into the lower 90's here with very little wind. I came home to find the the pond looking like this after work, lots of very tiny bubbles coming to the surface along the edge of the pond with a bubble film covering 90% of the pond. My pond has been turbid for the last month due to rain but has started clearing quite a bit in the last few days, an algae bloom has been kicking in. Whatever this film was covering most the pond it appears to have been short lived.
I did catch one more RES with the same symptoms yesterday, it was caught the same shallow area the first one was caught, an area where they typically spawn. I also caught several other RES, a few SMB, YP, and GSH yesterday with no symptoms like this, very weird.
One thing to note, I have tons of freshly hatched fish fry along the edges of the pond. They appear to be mostly GSH fry with possibly RES fry mixed in, at 5-7 mm it is hard to tell what they are at this point. The first wave of GSH that hatched 3-4 weeks ago are already 1"+ now.
My water clarity 5 days ago was 5-6", in the last few days it jumped up to 11-12".
