Low magnesium

[scotty333]

Hi guys

On Tuesday my mag reading at lfs was 1320 and calcium 400
Yesterday I tested it to 1170 and 415 calcium
Today I get 1070 and 410

Kh remains stable since Tuesday at 8.1

Since Thursday I’m dosing triton method , 12ml doses of kalk, mag and calcium

My sps have polyp retraction , lps and softies all fine

I want to raise mag dose to get around 1250 on my test kit ( Salifert) , that way it can be 100 +/- to be in range

Now I know mag is difficult to test for and I can’t get to lfs before Tuesday to confirm I think I’m going to add an extra 8ml per day of triton mag but how much will that increase from 1070 if that’s correct ?

Water volume 400 ltr

 

[TokenReefer]

See if you can get some more consistent test results. I've been in this boat; Salifert led me astray but it's not their fault. Mg it seem is a finicky test. Just be careful not to over do it based on a lower than actual number or vice versa. Go slower fme and good luck

 

[VDC]

I would buy another test kit, I use Red Sea.

Mg is not hard to test for.

To raise mag to 1250 from 1070 using b ionic (personal preference) you would need 1900 ml/64 ounces of product.

 

[gbroadbridge]

Hi guys

On Tuesday my mag reading at lfs was 1320 and calcium 400
Yesterday I tested it to 1170 and 415 calcium
Today I get 1070 and 410

Kh remains stable since Tuesday at 8.1

Since Thursday I’m dosing triton method , 12ml doses of kalk, mag and calcium

My sps have polyp retraction , lps and softies all fine

I want to raise mag dose to get around 1250 on my test kit ( Salifert) , that way it can be 100 +/- to be in range

Now I know mag is difficult to test for and I can’t get to lfs before Tuesday to confirm I think I’m going to add an extra 8ml per day of triton mag but how much will that increase from 1070 if that’s correct ?

Water volume 400 ltr

It is impossible for Mg to drop like that unless your salinity is dropping significantly or there is a test error.

Check your salinity with a calibrated device.

 

[Garf]

Hi guys

On Tuesday my mag reading at lfs was 1320 and calcium 400
Yesterday I tested it to 1170 and 415 calcium
Today I get 1070 and 410

Kh remains stable since Tuesday at 8.1

Since Thursday I’m dosing triton method , 12ml doses of kalk, mag and calcium

My sps have polyp retraction , lps and softies all fine

I want to raise mag dose to get around 1250 on my test kit ( Salifert) , that way it can be 100 +/- to be in range

Now I know mag is difficult to test for and I can’t get to lfs before Tuesday to confirm I think I’m going to add an extra 8ml per day of triton mag but how much will that increase from 1070 if that’s correct ?

Water volume 400 ltr

Certainly looks like test error, if calcium and Alk are still ok. I've got Randy's DIY salinity calibration recipe in my sig if interested.

 

[scotty333]

It is impossible for Mg to drop like that unless your salinity is dropping significantly or there is a test error.

Check your salinity with a calibrated device.

Salinity 1.025.5

 

[scotty333]

Certainly looks like test error, if calcium and Alk are still ok. I've got Randy's DIY salinity calibration recipe in my sig if interested.

I’ll use rodi to recalibrate

 

[Garf]

I’ll use rodi to recalibrate

May be ok, maybe not, depending upon the device. Usually more accurate to calibrate to a known standard at the target value. But more likely a magnesium test error in this case.

 

[scotty333]

Now I’m getting mag at 1020 so I’m almost certain it’s low

Edited

 

[Garf]

Now I’m getting 1020 so I’m almost certain it’s low

How about new salt water at the same salinity?

 

[Randy Holmes-Farley]

Now I’m getting 1020 so I’m almost certain it’s low

I’m certain your magnesium values are unreliable. They are all over the place in ways that are impossible to be real.

Agree with Garf: measure some new salt water.

 

[scotty333]

I’m certain your magnesium values are unreliable. They are all over the place in ways that are impossible to be real.

Agree with Garf: measure some new salt water.

I’ve got some nsw but am away until Tuesday

 

[scotty333]

Icp by triton 1362 11th June

 

[Randy Holmes-Farley]

Icp by triton 1362 11th June

Then it almost certainly is very close to that now and is fine.

 

[scotty333]

Same as nsw, will icp once a month and top up accordingly

 

[gbroadbridge]

Same as nsw, will icp once a month and top up accordingly

I would not bother routinely measuring Magnesium unless you are certain your tank has unusually high consumption.

Dosing Mag at around 10% the rate of Calcium will work out fine. I simply add Mg to my Ca dosing.

I perform an ICP about every 6-9 months just to make sure no contaminants are building up in the tank.

 

[scotty333]

I’m running triton method so it’s being dosed as per the method

 

[ReefStable]

I would try a new test kit. I personally like the Red Sea Mag kit. The Hanna Checker is likely consistent as well, though I don't know the accuracy.

Typically speaking, Mag shouldn't drop like that. Though I have seen magnesium drop from 1300 to 1100 or so fairly quickly before, it usually levels out right away. I couldn't tell you the cause of that either.

So I wouldn't react too fast, but get a new test kit and try to validate the numbers a bit more before reacting to the reading.

 

[Randy Holmes-Farley]

ng, Mag shouldn't drop like that. Though I have seen magnesium drop from 1300 to 1100 or so fairly quickly before, it usually levels out right away. I couldn't tell you the cause of that either.

That is test error. Such errors are very common and is why I do not recommend wasting time and energy testing magnesium and then having to react to test errors.

 

[scotty333]

Lfs will check tomorrow