Yes, the Xiaomi Smart Pet Fountain 2 can use clean tap water; however, it is highly recommended to use purified or mineral water for the best results. Hot water or boiling water should not be used. Using purified water helps prevent the buildup of minerals and contaminants that can accumulate over time, ensuring that your pet has access to fresh and clean drinking water. Tap water contains chlorine, sediments, or other impurities that could affect the pet fountain's performance and the water's quality. Additionally, filtered water can help extend the lifespan of the pet fountain's components, including the pump and filters, ultimately leading to better hygiene and healthier hydration for your pets. Regularly monitoring and replacing the water will further enhance their drinking experience.