First off, I ask that you forgive me for responding so late, since the page hasn't had any real traffic for a while I've been forgetting to check on it. I will try to do better in regard in the future.
Sorry for the confusion, the fish are not visible until after they fishing minigame has been succesfully completed, you have to go off of the direction towards which the rope is being pulled. The light does not attract the fish but it does attract *the other thing* you do not wish to meet. I am grateful for your patience and feedback, I will look into communicating this information better for the next update! ...Whenever that happens. Have a good rest of your day! :D