i`m switching to chlorine(cheaper/easy to get/clearer water) and my question is on the use of trichloro-s-triazinetrione-its one of those 4 in 1 granular chemicals. My nieghbor uses it in his tub and has clean, clear water and its easy to mantain and he`s never had any problems. So i thought i`d try it and bought some( haven`t used it yet). After looking through my manual it says not to use tri-chlor chlorine, is this the same thing and does anybody know why not to use it.? thanks