Use a magnet. You can purchase one from an auto parts store or Harbor Freight. They come on a telescoping handle so you can move it around in the tank.
The piece of iron probably won't hurt anything but you will get rusty hot water. That will be an issue for dish washing and bathing.
HR18 inch reach25 inch NAPA telescoping magnetLeRoy
Homeless by Choice
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2015 Chevy 3500, Duramax, 4X4, DRW, Crew cab, Long bed
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