You're right! This is a great way to remember the different types of fish migration patterns. Here's a breakdown:

* Anadromous: These fish are born in freshwater, migrate to the ocean to mature, and then return to freshwater to spawn. Think of salmon.

* Catadromous: These fish are born in saltwater, migrate to freshwater to mature, and then return to saltwater to spawn. An example is the American eel.

* Diadromous: This term covers all fish that migrate between saltwater and freshwater. So, it includes both anadromous and catadromous fish.

It's a bit like a Venn diagram – anadromous and catadromous are subsets of diadromous.