Matsya Purana — Rite and Layout for Consecrating Ponds
ततो मङ्गलशब्देन भेरीणां निःस्वनेन च अञ्जसा मण्डलं कुर्यात् पञ्चवर्णेन तत्त्ववित् //
tato maṅgalaśabdena bherīṇāṃ niḥsvanena ca añjasā maṇḍalaṃ kuryāt pañcavarṇena tattvavit //
Then, amid auspicious utterances and the resonant sound of kettledrums (bherī), the knower of the principles (tattva) should promptly draw the maṇḍala using the five colours.
This verse is not about Pralaya; it focuses on auspicious ritual procedure—beginning the maṇḍala with benedictions, drums, and the prescribed five-colour method.
It implies that public and domestic sacred works (like temple rites, consecrations, or building ceremonies) should be initiated with proper auspicious observances and expert guidance (tattvavit), ensuring dharmic order in undertakings.
It prescribes the maṇḍala-vidhi: draw the ritual/architectural diagram promptly and correctly using pañcavarṇa (five colours), accompanied by maṅgala chants and bherī drums—standard markers of an auspicious commencement in Vastu and temple rites.