This is a highly debatable topic, but our understanding is that grit is only needed in birds who do not hull their seeds. Most finches, for example, eat the seed whole and use a small amount of grit to help digest the seed.
However, if anyone were to look into our flock's bowls, you would find hulls from the seeds that are uneaten. You see, most hook bills remove the outer casing and just eat the meat of the seed. They don't need assistance in digesting the meat of the seed. Also, with a well-balanced diet, birds don't need grit as a source of Calcium.
Unfortunately, we have heard of many birds, especially budgies/parakeets, who have compacted their crops full of grit. This can cause complications because the grit won't digest, the bird will stop eating, or can even die.
Therefore, we do NOT recommend grit.
(Our Board-Certified Avian Vet would concur on this!)
© TLA 2009