Depending on what remediation tap water has been through and where it is sourced Trace metal levels can drop to some very low levels, take for instance Manganese and Iron, both of these are present at quite decent background levels but if the levels are high then when it gets to a water treatment plant sometimes they will add Aluminium compounds that sequester/flocculate these metals out of solution, other compounds may be used to strip further contaminating elements out the water if present and these may take some of the more desirable metals with it, not always but sometimes. The reason for doing this for Manganese and Iron is that levels that are beneficial for plants will make water taste foul, 0.05ppm of Manganese will do this, not only does it adjust the flavour but it can also cause brown staining to laundry, everyone likes their whites white so it’s remediated for so strong detergents/oxidising compounds are less likely going to be entering the sewer system causing its own set of problems. It is costly to provide clean potable water but sometimes it’s worth the expense to both domestic and industrial end users. No one likes brown water out the tap, too much mystery for those that don’t know or don’t care to know! Personally I freaked out as a kid having to take a bath in brown water out the tap (did you know you can hide tasty brown water in a cup of tea quite easily) while staying in some idyllic getaway in Granton on Spey (early 70’s, most probably a Skiing trip to Aviemore, back in the day when it was single track road with passing places just north of Perth to get there), remembered Dad muttering (protesting really) something Peat something something Peat and just to get on with it and be lucky the waters hot!
Talking about Holidays, I’ve never been but if you look up Trip Advisor or other tourist Feedback sites for Vilnius in Lithuania the comments are replete with complaints of how bad the water tastes, not just bad but like really bad, the funny thing is Lithuania gets all its water from 5 different aquifers and they are all rich in Iron and Manganese and other metals, entirely safe to drink once it’s been chlorinated and probably quite good for you (there’s a spring somewhere near one of these aquifers that they actually bottle the water neat and sell on as a health tonic). The other reason I mention this is that I seem to recollect someone from Lithuania posting about never needing to add Traces to his tank and that we are all mad for overdosing our tanks with EI levels of fertiliser when it’s not needed. I should point out that I might be remembering the forum interaction differently or even remembering a response I never posted (save me Darrel
@dw1305) but my thoughts were they should have looked at the water report first before commenting or at least paid attention to state of their rusty taps.
Not all water is the same, you can’t trust you have all that is needed unless you have access to a detailed water report that actually lists the concentrations present in the water in both high and low numbers that you can deduce an average. If you don’t know then it’s always best to at least add some.
Ramble over!