So... I vacuumed out the black stuff- sorta. The water is as black as charcoal, the sand was stained black, and the swords roots were pitch black too. Next weekend, try the next section.
Poo.. stinky. Also attacked the cat with two brushes, one effective that she HATES, the other not so great for getting her fur out, but that must feel heavenly. When I got done with the second one, she had her tongue poking out. After the first one..... she ran away and tried to claw me. I have to wonder if it bothers her, I try to be gently and it does get out that under coat.