I feed them a tin of tuna every few days to increase the protein in their diet. After doing this for a couple of weeks they no longer rip off my fingers for it.
In the interest of ensuring they get the right mix of foods, I just give them a wide variety of grains. Wheat, Peas, Lupins, Black Sunflower Seeds, Corn, Lucerne Chaff, and A free feeder of Shell Grit.
I'm planning on adding sesame seeds to this soon, and if I ever get down to the beach, bringing home some seaweed thats washed up (because I think thats the kind of kelp we need).
As for the mix, it was 2 wheats to 1 of any other kind of grain (gave roughly 18% protein) but I'm also planning on slowly modifying it. For example they just finished off the mix, and I noticed that there were heaps of peas left over, whereas they used to go nuts for peas. So I assume that there are too many peas inthe mix, so next time, I will make it with less peas.