Watch the Zep mildew remover around chrome-on-bronze. Dissolves the chrome into a purple/blue stain onto the glass. Whoa, been there done that! White vinegar saved the day on the glass to remove the stain, too late for the chrome on bronze nuts. The Zep didn't get stain out.
Zep does work fastest in my test trail on the black mildew spots on the helm seats plastic armrests and bloom under hardtop, then in order of speed: Spray Nine, Clorox Cleanup, white vinegar(2parts)/lemmon juice(one part)/water (2 parts) combo (from NEM). The combo never id get the last remnants.
Just keep Zep away from metal. And wear latex or nitral gloves on all these, did a number on my skin, cracked the skin at fingertips.