That sounds wonderfully poetic—imagine a gentle violin line echoing the ripples as the fish feel the pull. A soft, slow Adagio in F‑major, maybe something like Debussy’s “Clair de Lune,” could set that calm mood, letting the stream’s rhythm match the heartbeats of the water. If you want something a bit more spirited, a light Mozart piano sonata could lift the energy, but the key is to keep the tempo steady so the fish can feel the pulse without being startled. What kind of fish are you thinking of catching?