Gather all your vegetables and chop them into small pieces and set aside. Then cut the fish into bite-size pieces and set aside.
Heat the oil in a 2 quart sauce pan on medium-high heat then add the leeks and bell peppers. Cook for 3-4 minutes, stirring occasionally until softened. Add the garlic, cook for an additional minute, and then add the tomatoes and coconut milk. Simmer for 5 minutes before adding the celery root and fish.
Continue to cook for 15-20 minutes before tasting, adding the lemon juice, salt to taste and stirring in the chopped herbs. Spoon into two soup bowls and serve immediately. Store any leftovers refrigerate, in a sealed glass container, for up to 3 days.