Testing the water would help develop a strategy to reduce the Cr(VI), but I understand that using Ferrous Sulfate and Lime is an industrial method. This means the mix can have a variety of stuff in it, so it likely works in most conditions.
I'm still waiting on the lime to come in the mail. Once that happens I'll begin testing my wastewater and post the results. Meanwhile the method is used by industry, but not proved by anyone in the HHO test world.
I know that S(IV) can reduce CR(VI) as well but I haven't found a suitable means of using it. The Sulfur you can buy in pure form is S(VIII) configuration so pure sulfur isn't the answer. When I do find it, it will be a sulfur compound, I only sure of that much.
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