foil will prevent rust inside a toilet tank.
Why the Claim Doesn’t Hold Up
Rust forms when iron or steel reacts with oxygen and moisture under suitable conditions.
Aluminum behaves differently because it normally develops a thin protective oxide layer on its surface. Under certain circumstances, aluminum can participate in reactions involving other metals, but the result depends on the materials and conditions involved.
Simply dropping aluminum foil into a tank of water does not create a reliable rust-prevention system.
It won’t repair corroding metal components, remove existing mineral deposits,
