Today I was talking on the above subject with my friend who is a brahmin & hails from Tirunelveli, , also abt the Mahamaham tank having wells similar to Wells in Ramaeswarm temple where theertha snam made after taking a bath there in sea. That time his wife told that they have never visited Rameswaram for theertha snanam, as my friend's parents are alive. I would like know from this forum is there any such practice is there ? If so, why?