The Prophet ﷺ and one of his wives used to take a bath from a single pot of water. (Shuʿba added to Anas' Statement "After the Janaba").
سَمِعْتُ أَنَسَ بْنَ مَالِكٍ يَقُولُ كَانَ النَّبِيُّ ﷺ وَالْمَرْأَةُ مِنْ نِسَائِهِ يَغْتَسِلاَنِ مِنْ إِنَاءٍ وَاحِدٍ زَادَ مُسْلِمٌ وَوَهْبٌ عَنْ شُعْبَةَ مِنَ الْجَنَابَةِ