Waterbear, that's really interesting.

It's been so long, I'd forgotten about it. But in the past I occasionally had nasty startups to do. At the time, I had access to 30% peroxide fairly cheaply in 15 gallon carboys. On a whim, I dumped an extra carboy in a nasty pool, just to see what it would do.

Fizz!

Basically, exactly the same thing as you describe happened, which was really nice. While chlorine will clean up swamps like that, it doesn't penetrate the goo layers well. The peroxide fluffed them all up so nicely, you could work with them.

I even have a vague memory of trying it with copper sulfate added first, which seemed to accelerate the fizzing.

But, I generally avoid such gooey cleanups, so it's not something I'd had occasion to think of for a number of years. However, at the homeowner level, you could use Baqua Shock, and probably cheaper than percarbonate.

PoolDoc