First, a quick reality check: manganese usually shows up with its buddy iron. Together, they form stains that laugh in the face of bleach. In small amounts, it’s not toxic, but nobody wants black specks floating in their drinking glass.
The problem is that manganese comes in two forms: dissolved (clear water) and oxidized (that brown gunk). Most cheap filters only catch the oxidized stuff, leaving the clear, sneaky manganese to ruin your day later. You need a filter that tackles both—otherwise, you’re just polishing a turd.
