At 8 weeks, I would mix some chick grit with chicken grit (2 sizes sold at feed stores) they might need the larger size. You can continue to offer it daily, but maybe only after noon, for example, so they are eating feed first. Since they never had grit before this time, they might just be loading their system, or the grit might be too fine to do them much good and now that grit is spread around the run in various poops.
Our chickens have grit available all the time. They mostly ignore it, but the level does go down. Once I didn't see the level change for weeks and weeks- I was worried they weren't seeking out the grit, so I gave them a treat of yummy stuff (scrambled eggs and other various bits) and sprinkled some chicken grit over it. I came back 20 minutes later and every single molecule of treat was consumed, except for the grit - I think they left every single bit of grit behind (appeared to have been licked clean though).
Our chickens have grit available all the time. They mostly ignore it, but the level does go down. Once I didn't see the level change for weeks and weeks- I was worried they weren't seeking out the grit, so I gave them a treat of yummy stuff (scrambled eggs and other various bits) and sprinkled some chicken grit over it. I came back 20 minutes later and every single molecule of treat was consumed, except for the grit - I think they left every single bit of grit behind (appeared to have been licked clean though).
