Combine half of the water with the psyllium husk. Mix and set aside.
In a large mixing bowl, combine the flours, yeast, salt and sugar. Add psyllium husk, remaining water and vinegar. Mix well until it all comes together. Remove to a lightly floured surface and bring dough together for several minutes, kneading until smooth. Dough will be a little sticky so the floured surface will help. Form into a ball and place in a lightly oiled bowl, cover with a damp tea towel and set aside in a warm place for 45-60 minutes until doubled in size.
Once dough has risen, tip it onto a lightly floured surface and knead gently whilst shaping it into a log to fit a 10 x 20cm loaf pan. Scatter seed mixture on bench top and roll dough over it, coating the outside. Place into the lightly oiled loaf pan, cover loosely and set aside for a further 45-60 minutes, or until doubled in size.
Pre-heat oven to 240°C (220°C fan-forced). Cut several slits on the surface of the dough and bake for 35 minutes. Tip out of the pan once cooked and allow to cool on a wire rack.