Fish swim between worlds — creatures of the deep appearing near the surface — and so they carry insights rising from the unconscious: intuitions, creative ideas, glimpses of truth. Catching a fish means seizing such an insight or opportunity; in folk tradition it is one of the happiest omens, promising provision and abundance.
A fish slipping from your hands suggests an elusive idea or chance not yet ready to be held. Dead or foul water spoils the omen, hinting at neglected emotional environments. Clear water teeming with fish is the dream at its most generous: a season of plenty approaching.