Matsya Purana 58.25

58.25

kūrmādi sthāpayenmadhye vāruṇyāṃ mantramāśritaḥ.
brahmāṇañca śivaṃ viṣṇuṃ tatraiva sthāpayed‌ budhaḥ.. 58.24 ..

Then, images of the turtle and other water animals should be established in the middle, after reciting the hymns of Varuṇa (the God of waters), and afterwards images of the Deities, Brahmâ, Śiva and Viṣṇu, should be established.—24.