In my tank, I have what appears to be 2 types of brown algae. One the fish eat, the other they don't. The other is also what kills snails. So far I've had bubbly brown stuff in my tank for most of the last six months. Scrape it off, it comes back in hours. Disturbing the substrate seems to increase it, so that's likely what has caused your outbreak.
__________________
Brad
|