Upendra: "The innumerable universes are generated from skinholes of this Kāraṇodakaśāyī Viṣṇu, and in each one of the universes the Lord enters as Garbhodakaśāyī Viṣṇu."
Prabhupāda: Again, after creation of the universes, He enters each and every universe. This universe is filled with water, half. What you are seeing, that is half only. And half is filled with water. In that water Viṣṇu again lying, expanding. This is Viṣṇu's power. He can expand in innumerable identities. That is also confirmed in the Brahma-saṁhitā. Advaitam acyutam anādim ananta-rūpam (Bs. 5.33). Ananta means unlimited, and rūpa means forms. He's expanding in unlimited number of forms. We are also expansion of His form. These jīvas, the living entities... He is expanding in two ways, svāṁśa and vibhinnāṁśa. Svāṁśa means Viṣṇu. One extension, expansion, is just directly He Himself. And another expansion is separated from Him. That separated from Him we are.