1.Combine chilli, garlic, rind, parsley and oil in a small bowl, season with black pepper to taste. Divide garlic mixture in half; refrigerate one half of the mixture, covered. Combine remaining garlic mixture with prawns and octopus. Cover, refrigerate for 1 hour or overnight.
2.To make dough, place buckwheat in a small heatproof bowl; cover with boiling water. Stand, covered for 30 minutes. Rinse under cold water; drain. Combine the warm water, sugar and yeast in a small jug, cover; stand in a warm place for 10 minutes or until frothy. Combine buckwheat and sifted flours in a medium bowl. Add yeast mixture; mix to a soft dough. Knead dough on a floured surface for 5 minutes or until smooth and elastic. Place dough in an oiled medium bowl. Cover; stand in a warm place for 45 minutes or until doubled in size. Halve dough. Roll each half into 15cm rounds; place on trays.
3.Meanwhile, preheat oven to 220°C. Lightly grease two large oven trays.
4.Bake pizza bases for 8 minutes or until partially cooked. Top with seafood mixture and tomato. Bake pizzas for a further 10 minutes or until bases are crisp and seafood is just cooked, drizzle with reserved garlic mixture.
5.Combine rocket, parsley and juice in a small bowl; season with pepper to taste.
6.Top pizzas with rocket mixture; serve immediately.