Preventing rust / monitoring for rust

After seeing rust as a common way of pool collapse, how do you monitor for it or prevent it?

General answers are good, but if anyone has specific experience: I have a steel side pool. The installer told me to put topsoil up against the bottom rail to prevent washout, so I’ve done that, but I’m worried about rusting underneath the soil. He told me not to put a tarp between the topsoil and pool as it would actually trap moisture.

so, just wondering overall how to keep on top of this.