In a large pot of boiling water, boil for approximately 40-50 minutes the sliced calamari until tender, remove to a separate medium-sized bowl with a slotted spoon.
Keeping the pot of boiling water add mussels and cook 3-6 minutes, remove to the same bowl with the calamari and add the shrimp to the boiling water and boil or 3-6 minutes, remove to the same bowl.
Drain the fish in the medium-sized bowl a second time just to remove excess liquid and let cool. Add the chopped celery, grated carrot, chopped olives, chopped parsley , olive oil and lemon juice. Gently mix to combine well.
Refrigerate for at least 2-3 hours to combine flavours.
Before serving add a little more olive oil (3-4 tablespoons) and salt if necessary, you could also add some extra chopped fresh parsley. Some people like a drizzle of Balsamic vinegar or extra lemon juice. Serve with crusty Italian bread. Enjoy!
Notes
Besides, shrimp, mussels, calamari or cut up halibut you could use crab, lobster, scallops or even octopus. Be sure to use the freshest seafood. Use taste, touch and smell to determine this. It should never smell off or have an extremely strong fishy smell. If it is sticky or very slimy it isn’t good either.Store the Seafood Salad in an airtight container it will keep for up to 3 days in the fridge.I don't recommend freezing it, because the seafood could have been previously frozen and it shouldn't be refrozen, plus with the addition of the chopped celery and carrot, they would probably become soggy rather than stay crunchy.