These acids resist staining by ordinary methods The following activity will teach students how to complete an Acid-Fast Stain and identify bacteria based on their different cell wall properties. The acid-fast stain is performed on samples to demonstrate the characteristic of acid fastness in certain bacteria and the cysts of Cryptosporidium and The acid-fast stain is performed on samples to demonstrate the characteristic of acid fastness in certain bacteria and the cysts of Cryptosporidium and