Make the aïoli by placing the garlic and egg yolks in a food processor or blender, adding the lime juice and processing briefly to mix. With the machine running, gradually add the olive oil in a thin, steady stream until the mixture forms a thick cream. Turn into a bowl, stir in the lime rind, and season with salt and pepper. Set aside.
Slice the potatoes thinly and brush well with olive oil. Sprinkle the slices with salt and pepper and cook on a hot barbecue for 8—10 minutes on each side or until tender and golden. Remove from the heat and keep warm.
Score the sea bass fillets, brush well with the remaining olive oil and cook, skin side down, on the barbecue for 3—4 minutes until just cooked, turning once. Remove from the heat and serve the fish, potatoes and aïoli garnished with lime slices and snipped chives.