Traces of corrosion or rust can be seen on the cartridge. Is that bad?

A slight misting up on the cartridge and the release thread is completely normal with frequent use in the water. It does not affect the release function, but rather is a purely visual flaw. Depending on the environment, it is also possible that a clearer dark gray layer of corrosion can be seen on the cartridge. However, this is also not a problem for the function, because a form of protective layer is deposited on the special alloy, which protects the cartridge from further corrosion.