'A challenge and an opportunity for evolution': The extreme, hidden life thriving in Earth's most acidic and alkaline lakes
"The most acidic natural inland waters are the lakes that lie in the craters of volcanoes, like Kawah Ijen in Indonesia. These lakes are so rich in sulfuric acid that they may have a pH as low as 0.1. To put this in context, fresh battery acid has a pH of about 0.7. "
