Garudapurana 1.220.3

1.220.3

tatparisamāpya pitāmahaprapitāmahavṛddhaprapitāmahakrameṇa pātrāṇāṃ manāk cālanam /
uddhāṭanaṃ kṛtvā--oṃ ye samānāḥ samanasaḥ pitaro yamarājye /
teṣāṃ lokaḥ svadhā namo yajño deveṣu kalpatām /
oṃ ye samānāḥ samanaso jīvā jīveṣu māmakāḥ /
teṣāṃ śrīrmayi kalpatāmasmin loke śataṃ samāḥ /
etanmantradvayena pitṛpātrodakaṃ pitāmahaprapitāmahapātre vṛddhaprapitāmahapātraṃ parityajya pitāmahaprapitāmahayorudakaṃ pavitrañca pitṛpātre kṣipet //

Having concluded that, slightly moving the vessels in the order of the grandfather, great-grandfather, and great-great-grandfather. / Uncovering them: "Oṃ, those ancestors who are united and like-minded in the realm of Yama, / may their world be svadhā, homage! May the sacrifice be prepared among the gods! / Oṃ, those my [ancestors] who are alive, united, and like-minded among the living, / may their prosperity be prepared in me in this world for a hundred years!" / With these two mantras, leaving aside the vessel of the great-great-grandfather, one should pour the water from the father's vessel into the vessels of the grandfather and great-grandfather, and pour the water and purifier of the grandfather and great-grandfather into the father's vessel.