I have a Triton Tagelus TA60 sand filter which was probably installed around 1998 or 1999. My first season with the pool was summer of 2000 and I have not changed the sand since the filter seemed to be doing its job until this year. Does anyone have any experience changing the sand on one of these filters? Do I have to remove the multiport valve in order to remove the sand? There does not appear to be a clamp, so I'm assuming it is threaded with the buttress type thread since it was manufactured after 1991. Also is there a special tool required to remove the valve or do you just grab the body of the valve and turn it to get it off?