There are thousands of temples all over India in different size, shape and locations but not all of them are considered to be in the Siddhantic way. Generally, the temples are located in a place where earth's magnetic waves pass through. In simple terms, these temples are located strategically at a place where the positive energy is abundantly available from the magnetic wave distribution of north/ south pole thrust.
Because of its location, where high magnetic values are available, the Main Idol is placed in the center, and also because they place a copper plate written with some Vedic scripts, which is buried, beneath the Main Idol's placement known as "Garbhagriham" or Moolasthanam, the copper absorbs the earths magnetic waves and radiates to the surroundings. Thus a person who regularly visits a temple and makes clockwise pradakshinam of the Main Idol's placement, automatically receives the beamed magnetic waves which get absorbed by his body. This is very slow and a regular visit will make him absorb more energy, known as positive energy. In addition, the Sanctum Sanctorum is completely enclosed on three sides. The effect of all energies is very high in here.
The lamp that is lit radiates the heat and light energy.
The ringing of the bells and the chanting of prayers gives sound energy.
The fragrance from the flowers, the burning of camphor give out chemical energy.
The effect of all these energies is activated by the positive energy that comes out of the idol. This is in addition to the north/south pole magnetic energy that is absorbed by the copper plate and utensils that are kept in the Moolasthanam.
The water used for the Pooja is mixed with Cardamom, Benzoine, Holy Basil (Tulsi), Clove, etc is the "Theertham". This water becomes more energized because it receieves the positive-ness of all these energies combined.
When persons go to the temple for Deepaaraadhanai, and when the doors open up, the positive energy gushes out onto the persons who are there.
The water that is sprinkled onto the people passes on the energy to all. That is the reason why, men are not allowed to wear shirts to the temple and ladies have to wear more ornaments because it is through these jewels (metal) that positive energy is absorbed in ladies. It is proved that Theertham is a very good blood purifier, as it is highly energized.
In addition, temples offer holy water (about three spoons). This water is mainly a source of magneto therapy as they place the copper water vessel at the Garbhagriha. It also contains cardamom, clove, saffron, etc to add taste and Tulsi (holy Basil ) leaves are put into the water to increase its medicinal value! The clove essence protects one from tooth decay, the saffron & Tulsi leave essence protects one from common cold and cough, cardamom and benzoine known as Pachha Karpuram , acts as a mouth refreshing agents. This way, one's health too is protected, by regularly visiting Temples !