Water is treated differently almost ever where, just as water is different every where. Daugherty's water has a high alkalinity but a low calcium, a quite high arsenic and a high PH. I could easily anticipate problems with Daugherty's water in the areas of low calcium in relation to a high Ph and high alkalinity. But his raw water is probably exceptional in some respects in comparison to water from the arid South West like Biffers water. Daugherty's water has half the TDS of Biffer's water. Most likely there is quite a bit more calcium in Biffers water and probably more carbonates.
Treatment plants use different oxidizers, IE. some use potassium permangenate and some use chlorine gas, some lime soften some do not, some use clay as a coagulant as well as polymers for flocculation some do not, or some use aluminum (alum) and some use ferric iron as a coagulant aid for flocculation plus polymers, some use a lot of chlorine, some inject CO2, some use ferric Hydroxide and some use ferric hydrochloride, most do not, some use mass amounts of aeration where some just ignore the chemicals and heavy metals in the water if they are under the maximum allowed by law. For disinfection some use chlorine and some use chloroamine, and some use new designer chemicals instead, some use much more than chlorine than is needed as does Duagherties municipal water treatment plant. I highly recommend an RO filter or the use of RO water to every reefer. Lots of stuff gets injected, pumped, poured and somehow added to or water to make it the mess it is, but it looks clean, and is bacteriologically safe and most of it will lather soap, so it is treated water as required by law. No one will likely ever have as much success with tap water as they will with good RO, or even better than that RODI water. either of which has been aerated and balanced as needed before mixing for there reef tanks.
