If you have nitrate, dissolved metals, arsenic in your water, you might be interested in a little GoFundMe campaign I put together, based on scaling down my 25 years of work as an environmental consultant (don't worry! I've recovered nicely). Anyway, please grab a cup of coffee and a notepad and spend some time on a snowy Sunday afternoon, and maybe contribute a bit and volunteer your water and time.
Using Elemental Sulphur, Iron and microbes to precipitate and adsorb dissolved heavy metal.
Then refreshing them every 6 months.
I don't know much and I didn't even do a google search, but the science behind what you explained makes sense to.
Sulfur turns to Hydrogen Sulfide, This then react to Iron Oxide and dissolved metals and semi-conductors and precipitate/adsorb them. The microbes that power this system will also devour 'bad microbes' and nitrates are also turned into nitrogen gas. The microbes that power this setup is nitrate reducing bacteria.