When my cousin was going to clean her pool before she started swimming, she found hard white traces all over her pool tiles. These hard water stains were not coming off with regular soap and water and she even tried vinegar but the stains remained. She then went online and found an article that explained how muriatic acid could clean even the toughest hard water stains from pool tiles. She tried these tips out and used all the safety precautions as mentioned in the article and was able to deep clean her pool tiles using this acid. I am now sharing the article here so you can also see the proper way to clean your pool tiles and remove stains using muriatic acid.