the Prophet said: "Indeed there is a Shaitan for Wudu' who is called "AI-Walahan." So beware of having misgivings about water."  

عَنِ النَّبِيِّ ﷺ قَالَ إِنَّ لِلْوُضُوءِ شَيْطَانًا يُقَالُ لَهُ الْوَلْهَانُ فَاتَّقُوا وَسْوَاسَ الْمَاءِ قَالَ وَفِي الْبَابِ عَنْ عَبْدِ اللَّهِ بْنِ عَمْرٍو وَعَبْدِ اللَّهِ بْنِ مُغَفَّلٍ