Magnesium keeps rising!

[Undersea Gardens]

So, I've dosing kalk for over a year now.... Just kalk. Using 2 different mag tests the numbers are always over 1500. I've read several threads on here talking about inaccuracies related to mag testing so I thought no biggie.
Recently I sent in an ICP test and it comes back at 1667. I've never added and mag on any form, I use IO purple and it never comes down.
RODI tds meter always shows zero. Any ideas where it's coming from?

 

[gbroadbridge]

So, I've dosing kalk for over a year now.... Just kalk. Using 2 different mag tests the numbers are always over 1500. I've read several threads on here talking about inaccuracies related to mag testing so I thought no biggie.
Recently I sent in an ICP test and it comes back at 1667. I've never added and mag on any form, I use IO purple and it never comes down.
RODI tds meter always shows zero. Any ideas where it's coming from?

Which ICP test?

 

[Undersea Gardens]

Which ICP test?

Fauna marin

 

[gbroadbridge]

Fauna marin

I believe IO purple has quite high Magnesium levels
If your Salinity is also high it would make the Mg even higher.

Have you double checked the Salinity?

 

[Undersea Gardens]

It does show salinity is high even though I've been calibrating at least once a week with brightwells solution. I'll get some new solution and adjust accordingly. Maybe mag range will come back to normal. Thanks

 

[gbroadbridge]

It does show salinity is high even though I've been calibrating at least once a week with brightwells solution. I'll get some new solution and adjust accordingly. Maybe mag range will come back to normal. Thanks

You can make your own DIY calibration solution very simply And cheaply following instructions in this article.

https://reefkeeping.com/issues/2004-06/rhf/index.php

 

[Randy Holmes-Farley Verified Community Expert]

It does show salinity is high even though I've been calibrating at least once a week with brightwells solution. I'll get some new solution and adjust accordingly. Maybe mag range will come back to normal. Thanks

What did they show it to be?

 

[Undersea Gardens]

What did they show it to be?

12391mg/l. Not sure what that converts to in ppt.

 

[Randy Holmes-Farley Verified Community Expert]

12391mg/l. Not sure what that converts to in ppt.

What is that value?

 

[Randy Holmes-Farley Verified Community Expert]

I was asking about salinity, but that value is off for anything

 

[TokenReefer]

Fwiw I calibrate every time I use my refractometer. It was a cheap one and I've seen it fall off after putting it down too hard on the table (accidentally). The 3 extra drops, check and screw turn before use is another step, sure, but it's a minor one and that minor extra effort outweighs in terms of benefits, imo

 

[Undersea Gardens]

I was asking about salinity, but that value is off for anything

So that's the reading for sodium. On the test it actually said that salinity was not measured. I kind of assumed that that reading would indicate a high salinity.

 

[Randy Holmes-Farley Verified Community Expert]

So that's the reading for sodium. On the test it actually said that salinity was not measured. I kind of assumed that that reading would indicate a high salinity.

Well, that is a very high reading for sodium. The salinity is likely very high, which makes magnesium very high.

 

[Undersea Gardens]

Thanks for your input guys. I'll be getting some new calibration fluid for sure

 

[rtparty]

Make up some new water and add 160grams of salt per one gallon of water since you’re using IO Purple. Let it mix for a few hours. Then measure with your refractometer. It should be around 35ppt. Might be 34 or 36 but shouldn’t be far off. If you get anything else crazy, your refractometer is definitely off