You can see a video of his process below. The experimentation started with fish tank clarifier, which is — apparently — mostly alum. Alum’s been used to treat wastewater for a long time.

It turns out that a hot solution of alum (ammonium aluminum sulfate), which is available in the spice rack of your local supermarket, will dissolve the steel drill bit without reacting with the brass.

In an Instagram video posted Friday morning, Ullman said there is a “Plan B” if the aluminum sulfate treatment (alum) treatment does not sufficiently reduce the sediment at the North Fork ...