Iv'e have had a few over the years white magic hydramaster lots of bells & whistles now have a base 20-45 with a heat exchange had this one the longest and out performs all the others. I work alone so I'm in control of my things. I'm only as good as the chems and units that I'm working with. I look at each job for what it needs. The unit is Dynachem from Cobb. jz.