Palytoxin is a potent toxin found in zoanthid species, a popular decorative coral used in private aquaria. Inappropriate cleaning procedure may lead to palytoxin poisoning by dermal contact and inhalation of water aerosols, affecting several organ systems. This is a case report of three family members admitted to a hospital with symptoms compatible with palytoxin poisoning after cleaning an aquarium. One of them had remarkable respiratory distress and needed oxygen therapy.