Yeast in tank :,(

I had something similar happen when I knocked a bottle over, only it is alcaholic yeast mix inthe tank.

I lost one of my Oto's but the dwarf puffers were ok.
 
I made a second bottle that acts as a gas seperator, so the co2 passes through fresh water before entering the tank, and have eliminated any yeast that I was seeing in the tank.

I had this happen twice in different tanks. I did the same thing and added a smaller bottle (gas seperator) now if the yeast gets over active it spills into the seperator
 
I used to have a DIY co2 system and shook up the bottle a little too much. I turn around and the water is super cloudy. After a few consecutive water changes, I found all my angels dead.
 
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