food help

[Wallace]

i have recently taken on a 3yr old african grey who to my knowlage has been fed primarily on sunflower seeds and monkey nuts (i know bad) ,he also had a cold/blocked nose & i have taken him to a avian vet who has given me antibiotics for his water and vitamins to suppliment his food

can you give me any advice on weening him onto fresh fruit and veg (he will take walnuts and brazils)

thanks in advance