Magnesium still dropping fast

[Rakie]

So despite my best efforts, my magnesium is still dropping at an ungodly rate. I've dosed a LOT of Brightwell Aquatics magnesium on top of my regular daily dose of ATI magnesium --

First time I posted this I was told my test kit was bad -- Test kit is NOT bad, confirmed by other tests from a friend, and an LFS -- Test kit is spot on.

I'm losing around 10ppm or more per day.

Sep 25 -- 1305ppm
Oct 1 -- 1230ppm

So where is my Mag going if it's not being taken up by corals at this rate?

System volume is around 50 gallons.

 

[FlyinBryan]

Are you running Kalk?

 

[Rakie]

Are you running Kalk?

No, just ATI Elements, no kalk. It's ATI's 2 part.

 

[Randy Holmes-Farley Verified Community Expert]

Aside from water changes with a mix lower than your aquarium, it is not possible to consume 10 ppm of magnesium per day.

Real consumption ratios are on the order of:

1 meq/L alkalinity (2.8 dKH)
18-20 ppm calcium
0-2 ppm magnesium

So real magnesium consumption is not generally more than 1/10th of the calcium depletion rate.

What salt mix are you using for water changes, and at what salinity?

Note that it takes large amounts of all magnesium additives to boost it a lot. Even the typical solid dry additives are only 10% magnesium by weight.

 

[Rakie]

I have done zero water changes since starting ATI, as the ATI system is based around zero water changes -- I will do them in the future, but I wanted the let the system establish first as consumption of everything has gone up and down dramatically.

So there have been zero water changes. Water is at 1.026, Red Sea blue bucket, and formerly Fritz RPM.

 

[Randy Holmes-Farley Verified Community Expert]

I have done zero water changes since starting ATI, as the ATI system is based around zero water changes -- I will do them in the future, but I wanted the let the system establish first as consumption of everything has gone up and down dramatically.

So there have been zero water changes. Water is at 1.026, Red Sea blue bucket, and formerly Fritz RPM.

I'd make a correction, then just monitor it and see what you need to do going forward. If you boost to 1350, it should not need more supplements for quite some time.

Many people think their magnesium is moving around a lot (as often up as down) but it is usually noise in the testing.

Use a calculator to determine the boost needed, not trial and error.

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, the magnesium in a two/three part is most often designed to keep magnesium steady, not raise it. So no matter the apparent volume added, if it is according to recipe you should not expect to see a big boost.

That said, I have no idea how much ATI uses or how they decided how much to use.

 

[Rakie]

FWIW, the magnesium in a two/three part is most often designed to keep magnesium steady, not raise it. So no matter the apparent volume added, if it is according to recipe you should not expect to see a big boost.

That said, I have no idea how much ATI uses or how they decided how much to use.

Yep, I know what you mean. I've dosed an entire 250ml bottle of Brightwell Magnesium should have raised me to 1450ppm -- it raised mag to 1305, only a 70ppm increase, which is half of what the bottle states.

It could definitely be noise in tests which are not nearly accurate enough -- But that noise is congruent from test to test, in both Salifert (two tests), and Red Sea. So while the tests may be off, all three tests were within 10ppm (which is like, one drop, that can easily be caused by different lighting or individuals interpretation of color). That coupled with no water changes is what made me think my mag is going somewhere -- be it by means of some manner of precipitation or something.

I've also only been on ATI Essentials since Sep 16th or 17th, definitely not long.