Matsya Purana — Catalogue of the Eighteen Puranas
चतुर्दश सहस्राणि तथा पञ्च शतानि च भविष्यचरितप्रायं भविष्यं तदिहोच्यते //
caturdaśa sahasrāṇi tathā pañca śatāni ca bhaviṣyacaritaprāyaṃ bhaviṣyaṃ tadihocyate //
It consists of fourteen thousand, and additionally five hundred (verses); and here it is declared to be a Purāṇa largely concerned with accounts of what is yet to come (future events).
This verse does not describe Pralaya directly; it classifies the Matsya Purāṇa by its size and notes that it is largely oriented toward accounts of future events.
Indirectly: by identifying the Purāṇa’s scope as future-oriented narrative, it frames the text as a source for anticipating coming ages and aligning royal/householder conduct with Purāṇic guidance elsewhere in the work.
None explicitly in this verse; it is a bibliographic statement about the Purāṇa’s extent and thematic character rather than Vāstu, temple rules, or ritual procedure.