Why cant clownfish get stung by anemones?

Clownfish are immune to the stinging cells of anemones due to a unique mucous coating on their skin, which prevents the anemone's nematocysts from firing. Additionally, clownfish engage in a behavior of rubbing against anemones to acclimate and develop this protective mucus layer. This mutualistic relationship benefits both species, providing clownfish with protection from predators and anemones with nutrients from the clownfish's waste.