"I heard AlIah's Messenger while he was being asked about water in open areas of the land, and predators and beasts come to it." He said: 'So Messenger of Allah said: 'When the water is two Qullah it does not carry filth.'"  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ وَهُوَ يُسْأَلُ عَنِ الْمَاءِ يَكُونُ فِي الْفَلاَةِ مِنَ الأَرْضِ وَمَا يَنُوبُهُ مِنَ السِّبَاعِ وَالدَّوَابِّ قَالَ فَقَالَ رَسُولُ اللَّهِ ﷺ إِذَا كَانَ الْمَاءُ قُلَّتَيْنِ لَمْ يَحْمِلِ الْخَبَثَ قَالَ عَبْدَةُ قَالَ مُحَمَّدُ بْنُ إِسْحَاقَ الْقُلَّةُ هِيَ الْجِرَارُ وَالْقُلَّةُ الَّتِي يُسْتَقَى فِيهَا