Matsya Purana — Cosmography of Śākadvīpa and Successive Dvīpas: Mountains
द्रोणस्य हरिकं नाम लवणं च पुनः स्मृतम् कङ्कस्यापि ककुन् नाम धृतिमच्चैव तत्स्मृतम् //
droṇasya harikaṃ nāma lavaṇaṃ ca punaḥ smṛtam kaṅkasyāpi kakun nāma dhṛtimaccaiva tatsmṛtam //
For Droṇa, the names remembered are Harika and again Lavaṇa. For Kaṅka too, the name Kakun is recalled, and likewise the epithet Dhṛtimat is remembered.
This verse does not discuss Pralaya; it preserves traditional memory of alternate names/epithets within a genealogical listing.
Indirectly, it supports the Purāṇic aim of preserving lineage and reputation—key for royal legitimacy and for householders who maintain family history (vaṃśa-smṛti) through recitation and record.
No Vāstu/ritual procedure is stated here; the verse is technical in a different sense—cataloguing names and epithets used in Purāṇic genealogical tradition.