Combine and marinate the seafood and vegetables in a non-reactive casserole fitted with a lid. Cover, and marinate in the refrigerator from 30 minutes up to 2 hours. You can check and stir after 30 minutes. The key to ceviche is to marinate the seafood long enough to cook it through by the citrus juice, but if you leave it in the marinade too long it will toughen it.

When it is finished, season with salt and pepper and serve chilled.