People of Pooram star are noted for their discipline, courage, sharp thinking and entrepreneurship.  They are people of integrity and popular in society. There is a separate shrine for Lord Subramania behind the sanctum sanctorum.  There are also shrines for Porpanai Vinayaka, Lord Dakshinamurthy holding a Veena, Lingoghbava, Brahmma, Durga, Chandikeswara, Nandi, Chaturthi Vinayaka, Sapthamadhas, 63 Nayanmars, Aiyanar, Kasi Viswanathar, Visalakshi, Saraswathi, Mahalakshmi, Jeshtadevi, Balamurugan, Navagrahas the nine planets, Bhairava, Sun, Moon, Nataraja and Nalvar the Thevaram-Tiruvasagam saints.

Pooram starrers worship in the temples seeking relief from problems they face. Also child boon seekers, those affected by mental disorders and other planetary effects pray the Sri Chakra in the Ambica shrine.

Presiding deity Lord Hari Theertheswarar is worshipped as the family deity of people residing in places around 150 kilo meter of the temple.  Mother Perianayaki graces with four hands facing south.  It is said that Mother Goddess was born to one belonging to Kattudayan Chettiar lineage.  Based on this belief, women of this community regard Lord Shiva as their son-in-law and worship Him covering their head with Sari – Mukkadu.

Poora Theertham is a spring in the world of Agni.  There are Shiva theertha, Naga theertha, Gnanabrahmma theertha, Indira theertha, Sri theertha, Skanda theertha and Guru theertha – seven theerthas in the Poora star region.  The temple is dedicated to Pooram star.  Those born in this star are advised to visit the temple as often as they could, on their annual star day, monthly star days, wedding days and Aadi Pooram day.

Chola king Kalmashapadan was much annoyed as he did not have a progeny even after long years of marriage.  He felt that he would have none to continue his services to Lord.  He appealed to Sage Agasthya who advised him to go to Tiruvarankulam and worship the Shivalinga.  The king came to this place but could not find the Shivalinga and sought the help of shepherds.  They told him that people carrying puja materials through this way fall down at a particular spot.  The king dug the spot when the earth began to bleed.  The Shivalinga was there.  The king attempted to kill himself for injuring the Lord.  Lord appeared, prevented the king from the attempt and offered darshan with Mother Parvathi in His wedding form.  The temple was built here then. The event took place on a Pooram star day.  He was also gifted with a male child.

There was a golden palm tree on the outer corridor of the temple yielding golden fruits.  It is said that the temple was built with the sale proceeds of the golden fruit.  Now, the tree is not there.  There is a pillar now.  The temple was built before the 12^th century and renovated by Cholas and Pandyas.  As the holy spring came from the head of Hara, it is called Hara theertham.  The place came to be known as Tiru Haran Kulam-Tiruvarnkulam.  Hara-Shiva.