Magnesium wont go up?

[MichaelReefer]

Kinda mistreated the tank for a few months due to some life stuff. I spent the weekend getting her back to normal. My magnesium was low so I dosed some Bionic. Six hours later and my apex tested and came out with no increase but a 3 point decrease? Why won't it go back up?

 

[ReefQuestCorals]

First what was your mag level and how did you test it?

Second how much did you add?

 

[MichaelReefer]

First what was your mag level and how did you test it?

Second how much did you add?

It is at 1100. I dosed 180ml per the instruction recommendation for gallons.

I apologise
My apex didn't update right and it looks like it only went up 7ppm? Is that normal? Should I dosed more than recommended?

 

[ReefQuestCorals]

It is at 1100. I dosed 180ml per the instruction recommendation for gallons.

I apologise
My apex didn't update right and it looks like it only went up 7ppm? Is that normal? Should I dosed more than recommended?

How much total volume are you working with? Need more information to really give advice. 180m in a small tank is different than a large tank.

IMO I wouldn't trust 1 source especially technology. I would confirm with a salifert or Hanna kit to ensure your accurately reading the proper levels.

 

[MichaelReefer]

How much total volume are you working with? Need more information to really give advice. 180m in a small tank is different than a large tank.

IMO I wouldn't trust 1 source especially technology. I would confirm with a salifert or Hanna kit to ensure your accurately reading the proper levels.

Redsea 525xl g2. I guestimate at 120 gallons of water volume but could be a bit less with rock and such i guess?

I guess I expected it to go up much higher with so much magnesium but it didn't. It was so small on the graph that it looked like it didn't go up at all

 

[ReefQuestCorals]

Redsea 525xl g2. I guestimate at 120 gallons of water volume but could be a bit less with rock and such i guess?

I guess I expected it to go up much higher with so much magnesium but it didn't. It was so small on the graph that it looked like it didn't go up at all

That specific mag calls for 1.5ml per gallon which would raise mag 100 ppm. So ultimately your total mag by your reading should show 1200

I would suggest verifying with another test kit before adding more. Just because your apex says it is a certain level doesn't mean it is.

 

[MichaelReefer]

That specific mag calls for 1.5ml per gallon which would raise mag 100 ppm. So ultimately your total mag by your reading should show 1200

I would suggest verifying with another test kit before adding more. Just because your apex says it is a certain level doesn't mean it is.

Salifert is coming up approx 1100

 

[Shirak]

From my understanding Mg testing is not very accurate. I think it's something like +-50ppm from the actual value. I think you are safe to dose again tomorrow then see where your testing reads.

For my system I like to have my test kits reading around 1400ppm. That way I know I am between 1350-1450ppm. I like to test all my parameters too right before I send off an ICP just to see how they match up when the results come back.

 

[MichaelReefer]

From my understanding Mg testing is not very accurate. I think it's something like +-50ppm from the actual value. I think you are safe to dose again tomorrow then see where your testing reads.

For my system I like to have my test kits reading around 1400ppm. That way I know I am between 1350-1450ppm. I like to test all my parameters too right before I send off an ICP just to see how they match up when the results come back.

Side note. I noticed since I dosed today my.PH is lower. Is that normal for dosing magnesium? It aligns with the time I added to the tank?

 

[Pod_01]

Side note. I noticed since I dosed today my.PH is lower. Is that normal for dosing magnesium? It aligns with the time I added to the tank?

Mg has no impact on pH… perhaps the pH probe needs cleaning and recalibrating…

pH is impacted by Alk and CO2 level in the water… in general less CO2 in the water will leads to higher pH.

 

[ReefQuestCorals]

Salifert is coming up approx 1100

Id go ahead and dose more then test again and see what happens

 

[Garf]

Side note. I noticed since I dosed today my.PH is lower. Is that normal for dosing magnesium? It aligns with the time I added to the tank?

Assuming your salinity is good at 35ppt and checked against an appropriate standard , can you check some new saltwater and see what that magnesium comes out at?

 

[Randy Holmes-Farley Verified Community Expert]

Assuming your salinity is good at 35ppt and checked against an appropriate standard , can you check some new saltwater and see what that magnesium comes out at?

That’s what I would recommend.

 

[MichaelReefer]

That’s what I would recommend.

What effect will lower salinity have with magnesium and my ph drop? I'm at 1.024

The magnesium def dropped by PH substantially. My tank has the same Trend generally. What should I do?

 

[Garf]

What effect will lower salinity have with magnesium and my ph drop? I'm at 1.024

Magnesium (and most everything else) will be lower by about 10%. Effect on pH will be minimal, or none existent if the alkalinity is buffered to a certain target anyhow.

 

[MichaelReefer]

Magnesium (and most everything else) will be lower by about 10%. Effect on pH will be minimal, or none existent if the alkalinity is buffered to a certain target anyhow.

Well I dosed the magnesium at the same time my ph began to drop? Seems to coincidental?

 

[Randy Holmes-Farley Verified Community Expert]

Well I dosed the magnesium at the same time my ph began to drop? Seems to coincidental?

Unless you used an inappropriate additive , magnesium will not impact pH.

 

[MichaelReefer]

Unless you used an inappropriate additive , magnesium will not impact pH.

So back to the salinity discussion. Mine is a bit low. Would that effect how the added magnesium works? I am slightly under 1024 (working on that now)

 

[Randy Holmes-Farley Verified Community Expert]

So back to the salinity discussion. Mine is a bit low. Would that effect how the added magnesium works? I am slightly under 1024 (working on that now)

No, nothing impacts magnesium addition impacts. Salinity directly impacts magnesium and everything else just because there is more of everything in saltier water.

 

[MichaelReefer]

No, nothing impacts magnesium addition impacts. Salinity directly impacts magnesium and everything else just because there is more of everything in saltier water.

So what would cause my magnesium to not increase as expected when adding it? I added approx 500ml more last night and barely got up 20 points? Should I continue adding at that rate? Confirmed via salifert and apex