Are you suppose to give pigeons grit? If so, what brand is the best? Does grit contain oyster shells too? And if not, should pigeons be given oyster shells?

I have been using a mixture of: broken granite, broken oyster shells, broken brick, charred wood, magnesium carbonate (athletic chaulk), and pick stone. Now that most of the birds have babies, they are really eating a lot of the grit. At times, they are going for the grit before the food.

So I just took a bird class & learned that grit with oyster shell is now considered toxic because of ocean metals. I can't find any grit without the oyster shell. This is my first pigeon - she's about 2 1/2 mo. She eats 50 percent Harrison's pellets, & 50 percent grain mix. The grain...

I found a local farm supply store that actually stocks pigeon stuff. I am going in the morning to get crushed oyster shells and grit. They stock Bay-more Red and Grey Grit. What (besides the color) is the difference in the two grits? Should I be leaning towards one or the other? I have...

Oyster shells & Grit, can you mix them? How do you all mix it and or use it? I would also like to know, can Oyster Shells be use in place of grit or should they have both?