Greys are noted for becoming hypocalcemic. You should always keep a mineral block in their cage. Like these other than I like the plain without flavors.
Flavored Mineral Treat Block - Large cuttlebone is not appropriate for lager birds. Your birds (all of them) require UBV (Vit B3) rays to utilize the calcium in food or supplements. Windows filter out the UBV rays, so they will either require 15-20 min three times a week outside or full spectrum lighting. There are several threads on AA about full spectrum lighting. Calcium is also high in Almonds, green leafy vegetables and other foods. Remember no dairy products or meats for birds - you can look up calcium rich foods.
Greys along with Pionis, macaws and Amazons are particularly susceptible to Aspergillosis. Take this to heart;
Aspergillosis in Parrots
Greys are also susceptible to fatty liver disease and atheroscleosis. Keep their diet lean and make sure they get as much exercise as possible - flying is especially good for a bird. (DUH!)
@aooratrix This is the dried fruit mix I use. No preservatives nor dyes. I only put them in my Jasper's bird bread.
Caribbean Bliss Bird Food | Great Companions
There is a lot to learn about a parrot for people who want to keep them as companions.