There's a difference between shallow and deep water.
When you cast your line, look where it lands. If it's in shallow water, you'll catch shallow-water fish, and if it's in deep water, you'll catch deep-water fish.
How about you try fishing in shallow water?
See if you can catch me a Forest Pondleaper. They like to swim in the shallow water under the bridge.
You got one!
Want to try for a deep-water fish?