Elevated Mg with Fauna Marin element dosing

[ChrissyK75]

This has happened to me twice now where I have gotten my ICP test results back and I begin dosing the elements that are deficient according to their recommendations. Within a day of dosing the recommended elements, my Mg skyrockets even though I have an upper limit shutoff of 1400 with Trident monitoring and dosing. Just wondering if anyone else has experienced this.

 

[Lasse]

Can you attach the two ICP reports and their recommendations anf how you does in reality? Do you know which elements that can interfere with the Mg method your Trident use?

Sincerely Lasse

 

[Randy Holmes-Farley]

Home testing of magnesium is very error prone. So much so that I do not recommend it for dosing control.

Did the home test match the icp before dosing?

 

[ChrissyK75]

Can you attach the two ICP reports and their recommendations anf how you does in reality? Do you know which elements that can interfere with the Mg method your Trident use?

Sincerely Lasse

This is the most recent ICP results. I usually just dose trace with Fauna Marin trace 1,2 and 3 mixed in with Alk and Ca dosers as recommended. I've been slowly switching everything over to Fauna Marin products including salt. I didn't want to do anything too fast. I did get a response on the FB Fauna Marin group that sulfur/sulfate can affect Mg so I'm guessing that's what is causing this as it was significantly deficient.

 

[Randy Holmes-Farley]

I did get a response on the FB Fauna Marin group that sulfur/sulfate can affect Mg so I'm guessing that's what is causing this as it was significantly deficient.

OMG, defintely a reason to leave facebook entirely.

NO, sulfate cannot EVER impact magnesium in a reef tank.

What can happen is that too much magnesium dosing with a supplement that is not chloride/sulfate balanced can impact sulfate. For example, using Epsom salt (magnesium sulfate) to boost magnesium will boost sulfate significantly more than magnesium, and since sulfate is not depleted, it can accumulate over multiple dosings.

 

[Randy Holmes-Farley]

This is the most recent ICP results. I usually just dose trace with Fauna Marin trace 1,2 and 3 mixed in with Alk and Ca dosers as recommended. I've been slowly switching everything over to Fauna Marin products including salt. I didn't want to do anything too fast. I did get a response on the FB Fauna Marin group that sulfur/sulfate can affect Mg so I'm guessing that's what is causing this as it was significantly deficient.

Your magnesium is fine, and definitely not low. It's way above ocean levels.

BUT, your salinity is quite low, and raising it will raise both sulfate and magnesium (and everything else). It might make magnesium too high, so definitely stop dosing magnesium and work to raise the salinity.

 

[Randy Holmes-Farley]

Note that the right-most column of that ICP report is NOT a recommended level. It shows what the level would be if you raised your salinity to 35 ppt. DO not target it.

 

[ChrissyK75]

OMG, defintely a reason to leave facebook entirely.

NO, sulfate cannot EVER impact magnesium in a reef tank.

What can happen is that too much magnesium dosing with a supplement that is not chloride/sulfate balanced can impact sulfate. For example, using Epsom salt (magnesium sulfate) to boost magnesium will boost sulfate significantly more than magnesium, and since sulfate is not depleted, it can accumulate over multiple dosings.

Note that the right-most column of that ICP report is NOT a recommended level. It shows what the level would be if you raised your salinity to 35 ppt. DO not target it.

I have been gradually raising the salinity and am now at 35ppt. But I’ve also been adding Elementals S with the Fauna Marin product according to their recommendations (see attached catch up recommendations from FM). They said over 4 days and I've done 3 of the 4 doses (~263ml x 3 doses). Holding on the 4th dose of Elemental S at this point.

 

[ChrissyK75]

I have been gradually raising the salinity and am now at 35ppt. But I’ve also been adding Elementals S with the Fauna Marin product according to their recommendations (see attached catch up recommendations from FM). They said over 4 days and I've done 3 of the 4 doses (~263ml x 3 doses). Holding on the 4th dose of Elemental S at this point.

For Magnesium testing I use the Trident and occasionally verify consistency with Salifert. The dosing is manually scheduled with a shut off programmed at 1400. So no Mg dosing has happened while I've been dosing Elemental S but I have been adding salt to gradually raise to 35ppt.

 

[Randy Holmes-Farley]

I'm very confused.

Stop adding sulfate. You already have more than normal based on your salinity and when you raise salinity, it will be above natural levels even with no dosing.

 

[Lasse]

So no Mg dosing has happened while I've been dosing Elemental S but I have been adding salt to gradually raise to 35ppt

But Elemental S also contains Mg and according to this source - every rise of S with 1 ppm will rise Mg with 0.71 ppm

Technical Data

Dosing Recommendation

• Compensating sulfur defi ciencies in reef aquariums.
• We recommend checking sulfur content regularly by a water test.
• 10 ml per 100 l (26 US gal) will increase sulfur content by approx. 7 mg/l (0.26 US gal).
• Attention: at the same time the magnesium content increases by 5 mg/l.
• Maximum daily dose: Do not increase sulfur by more than 20 mg/l per day.

And I have read the PDF and beside all Mumbo Jumbo (IMO) about different ratio - i do not understand the recommendation - especially for the macro elements. All macro elements is more or less in range if we consider your low salinity and the advices state no need for action. IMO - its the first I would try to fix. 31.2 psu is low.

You should rise your S with 1055 ml elemental S. Every ml of this compound contain 70 mg S (calculated from
10 ml per 100 l (26 US gal) will increase sulfur content by approx. 7 mg/l (0.26 US gal).)
But it also means that you ad 50 mg Mg per ml (calculated from Attention: at the same time the magnesium content increases by 5 mg/l.)

1055 ml added means that you also will ad around 52750 mg Mg!

What I understand - your aquarium is around 1000 L - this means that you will rise the already high Mg with around 53 mg/L (app 53 ppm)!! if you follow the recommendations of dosing S

Sincerely Lasse

 

[Randy Holmes-Farley]

Wow, what a poorly named product.

Idea: let’s resell Epsom salt as an expensive sulfate supplement.

Staff scientist: wouldn’t sodium sulfate be better?

Money guy: it costs more, why would we?

 

[Randy Holmes-Farley]

Is that what the FB person was saying, that dosing sulfate raises magnesium? That’s certainly not normally true, but with that Fauna product it appears to be since they apparently cheaped out on the composition.

I misunderstood your post on what was low and what was being dosed. Sorry about that.

Nevertheless, stop dosing sulfate in any form.

 

[ChrissyK75]

Is that what the FB person was saying, that dosing sulfate raises magnesium? That’s certainly not normally true, but with that Fauna product it appears to be since they apparently cheaped out on the composition.

I misunderstood your post on what was low and what was being dosed. Sorry about that.

Nevertheless, stop dosing sulfate in any form.

I did stop dosing the sulfate and Mg is coming down to where I prefer to keep it. If I'm understanding correctly, if my salinity is where it should be the sulfate should follow. Thanks for the info! :)

 

[Randy Holmes-Farley]

I did stop dosing the sulfate and Mg is coming down to where I prefer to keep it. If I'm understanding correctly, if my salinity is where it should be the sulfate should follow. Thanks for the info! :)

Yes, that is correct. :)