I have a many year-old supply of Charlie Carp (fish emulsion) fertilizer that has "gone off". Namely, it has a strong ammonia smell. It's "commercial strength", meaning it's very concentrated.
Is it a good idea to use this? I've tried it on a few plants, and it didn't kill them, but I'm wondering what chemical change has happened, and if the ammonia might be killing off beneficial soil micro-organisms.