"Any insights from the other metals analysis? There are highs and lows but we all seem to be more or less in the same ballpark"
So I am just beginning to track this stuff. I know that Zn kills fish fast so I watch that pretty close along with copper. Unfortunately, we gain the most information when something goes wrong. When someone tells me their birds nest just went up in smoke and they don't know why, I will look at your metal and other history and try to figure out if it was chemical in nature or not.
The patterns and comparisons I see between everyone's tanks may yield some useful information for the future of reefing.
Ok so now a little background and then I have to act like I'm working for a little while.
Since the metals and salts do not evaporate along with the water in our tanks, We build up stuff in our tanks that we try and mitigate through water changes. The problem arises when we are not starting with clean water from our RO/DI that we use not only for salt water but top-off as well. If we are leaving lets say...a little Cadmium in our water that our filters miss either because they are old or cheap. Over time that Cd will theoretically increase in concentration unless something consumes it. It is the minor build up of cadmium that may torch your beloved animals and that buildup is what I want to monitor. (not just Cd, but that is a nasty one. Not a lot in our water though)