Ugh! If you have been invaded by silverfish, an insect with a silvery light grey color and fish-like appearance of its movements, you know you want to get rid of them. They love dark basements and bathrooms. They don’t love the scent of citrus. To send these critters packing, place some ground-up orange, lemon, and grapefruit peels wherever you see them. The limonene compound in them is toxic to these insects.