For my studies the extra calcium will harm their processing organs. But those studies didn’t show issues for a couple of years. There are several schools of thought. 1) give all feed with no calcium and just offer egg shells and oyster shells in separate container. 2) feed layer rations and worry about health issues down the line. 3) feed layer rations and get rid of the rooster

. Jk
But even if you have 2 separate bowls one with layer rations and one without, there is nothing keeping him from eating the layer ration one.