no on grit, it causes more harm then good, it causes crop impaction, tiels like other parrots Hull their seeds, The only birds who need it are like chickens, pigeons, ones who eat the seed whole.
Yes on Cuttlebones - I use a 2 in 1 its a cuttle bone on the inside and mineral block on the outside
and yes Millet is good for them it has alot of vitamins and minerals, It's great for a new bird in a new environment normally that's all a new bird will eat for the first couple of days being some where new, it also helps with the stress of molting
mine get it a couple times a week
Alot of people and websites say it's fattening but it's a natural product. I've researched it many times and always find all the minerals and vitamins that are in it. and thats its a good healthy snack/ treat
how much and how often you give your bird millet is up to you.