The Prophet ﷺ used to take a bath with one Saʿ up to five Mudds (1 Saʿ = [??] Mudds) of water and used to perform ablution with one Mudd of water.
سَمِعْتُ أَنَسًا يَقُولُ كَانَ النَّبِيُّ ﷺ يَغْسِلُ أَوْ كَانَ يَغْتَسِلُ بِالصَّاعِ إِلَى خَمْسَةِ أَمْدَادٍ وَيَتَوَضَّأُ بِالْمُدِّ
The Apostle of Allah ﷺ performed ablution with one Mudd and took bath with a Sa' up to five Mudds.
كَانَ النَّبِيُّ ﷺ يَتَوَضَّأُ بِالْمُدِّ وَيَغْتَسِلُ بِالصَّاعِ إِلَى خَمْسَةِ أَمْدَادٍ
"I heard Anas bin Malik say: 'The Messenger of Allah ﷺ used to perform Wudu' with a Makkuk (cup) and Ghusl with five Makkuks (cups).'" (Using translation from Nasāʾī 73)
سَمِعْتُ أَنَسًا يَقُولُ كَانَ رَسُولُ اللهِ ﷺ يَتَوَضَّأُ بِالْمَكُّوكِ وَكَانَ يَغْتَسِلُ بِخَمْسِ مَكَاكِيَّ
"I heard Anas bin Malik say: 'The Messenger of Allah ﷺ used to perform Wudu' with a Makkuk (cup) and Ghusl with five Makkuks (cups).'" (Using translation from Nasāʾī 73)
سَمِعْتُ أَنَسًا يَقُولُ كَانَ رَسُولُ اللَّهِ ﷺ «يَتَوَضَّأُ بِالْمَكُّوكِ وَيَغْتَسِلُ بِخَمْسِ مَكَاكِيكَ»