Looks like serious nute burn to me. It's natural after a burn for the leaves to die, in time...sometimes it's a slow death, other times it's quick. You flushed them, that's good. I've found that some plants just do not like fish emulsion. I had three Afghanis that loved it and one that just couldn't handle it. How old are your plants? I'm finding more and more people have to wait a little longer before giving nutes if they are using CFL's. Keep an eye on their new growth, as long as that's ok, your plants should be ok. Peace!