SB 12.4.3

tad-ante pralayas tāvān
 brāhmī rātrir udāhṛtā
trayo lokā ime tatra
 kalpante pralayāya hi
Synonyms: 
tat-ante — after those (thousand cycles of ages); pralayaḥ — the annihilation; tāvān — of the same duration; brāhmī — of Brahmā; rātriḥ — the nighttime; udāhṛtā — is described; trayaḥ — the three; lokāḥ — worlds; ime — these; tatra — at that time; kalpante — are prone; pralayāya — to annihilation; hi — indeed.
Translation: 
After one day of Brahmā, annihilation occurs during his night, which is of the same duration. At that time all the three planetary systems are subject to destruction.