 Cleaner fish interaction durations and memories of reoccurring clients are influenced by the neuroendocrine system of the fish, involving hormones arginine vasotocin, Isotocin and serotonin.Conspicuous coloration is a method used by some cleaner fish, where they often display a brilliant blue stripe that spans the length of the body.Other species of fish, called mimics, imitate the behavior and phenotype of cleaner fish to gain access to client fish tissue.