You received some good advice but I know it hasn’t been satisfactory. I really think you are wasting your effort. I’ll share some thoughts, but apologize because I know I am not helping with your aim to hit an mag number.
Alkalinity is worth a lot of effort to hit a fairly narrow range and keep it stable. Thankfully test kits are pretty accurate. I test Alkalinity daily or 2x daily when I am trying to dial it in and then weekly when I have it stable to confirm.
Calcium is worth less effort. Corals thrive in a wide range. Test kits are reasonably
accurate so still useful but not worth messing with as long as it’s within reason. I test a handful of times per year.
Magnesium is worth the least effort because corals thrive in a wide range, it changes very slowly and test kits are horribly inaccurate. I never test anymore. I do look at the results from my occasional ICP but rarely do anything in response except change my next dose up or down.
I know this thread was shared before, but I’ll include it again in case you missed it. Best of luck.
OK, this thread has been many years in the making, and I'm posting it here since folks in the chem forum are probably already tired of all the threads relating to problematic magnesium testing. I'm going to propose a method, let's call it the Randy Magnesium Method, or RMM for short. All good...
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