Black detritus?

[MarkoD]

i just harvested a bunch of cheato out of my refugium and vacuumed the button. what i pulled out was black detritus and it smelled terrible.

it was just sitting at the bottom with 0 light and almost 0 flow on it.

any idea what kind of bacteria would have caused it to turn black?

[Cugio]

Sounds like dead plant matter to me.