EXTREME Magnesium Consumption

[gizmodo]

System Volume: 20 Gallons
Alk: 8.8
Calc: 400
Mg: 1080-980
PH: 8.2
-Mg consumption of ~50ppm a day
-Daily dosing 80ml of 460g/L solution
-All other parameters stable.
-Upping to 100mL/day
Help!

 

[Randy Holmes-Farley]

Well, 2 ppm per day is extreme magnesium consumption, and in that cause, it takes an uptake of 20 ppm per day of calcium and about 3 dKH per day of aljk to achieve it.

50 ppm per day is unquestionable test error or a massive drop in salinity.

 

[gizmodo]

Well, 2 ppm per day is extreme magnesium consumption, and in that cause, it takes an uptake of 20 ppm per day of calcium and about 3 dKH per day of aljk to achieve it.

50 ppm per day is unquestionable test error or a massive drop in salinity.

I've had 3 other people get the same result as me. 2 new test kits and different brands. Still reporting the same results. Salinity is increasing somewhat stable, climbing about 0.001 per month

 

[gizmodo]

I've had 3 other people get the same result as me. 2 new test kits and different brands. Still reporting the same results. Salinity is increasing somewhat stable, climbing about 0.001 per month

I should clarify. If I do not dose. The drop will be 50ppm. At 50ml/day it is dropping 1ppm a day

 

[Randy Holmes-Farley]

I've had 3 other people get the same result as me. 2 new test kits and different brands. Still reporting the same results. Salinity is increasing somewhat stable, climbing about 0.001 per month

It doesn't matter who got what result, it is completely impossible for 50 ppm of magnesium to be consumed in one day in a reef tank.

A salinity drop from sg = 1.0264 to 1.0254 would do it, however.

What product are you dosing?

 

[gizmodo]

It doesn't matter who got what result, it is completely impossible for 50 ppm of magnesium to be consumed in one day in a reef tank.

A salinity drop from sg = 1.0264 to 1.0254 would do it, however.

What product are you dosing?

Seachem Reef Advantage. If it helps my phosphate was higher than my nitrate for a while and had to start dosing Nitrate. No idea how it was possible but it was. LFS confirmed

 

[Randy Holmes-Farley]

50 ml of a 460 g/L solution of Seachem Reef Advantage magnesium contains 23 g of product. That much is claimed by Seachem to raise magnesium by 23 ppm in 20 gallons of water.

I expect you have a magnesium testing issue, not least of which is the initial reading at 800 ppm. Magnesium just doesn't get that low, unless you are doing water changes with a mix that is grossly mismanufactured.

What salt mix are you using and have you measured it?

I know you don't believe it, but I guarantee that your tank is not consuming 50 ppm per day. There is no chemical mechanism that allows that much decline.

 

[gizmodo]

50 ml of a 460 g/L solution of Seachem Reef Advantage magnesium contains 23 g of product. That much is claimed by Seachem to raise magnesium by 23 ppm in 20 gallons of water.

I expect you have a magnesium testing issue, not least of which is the initial reading at 800 ppm. Magnesium just doesn't get that low, unless you are doing water changes with a mix that is grossly mismanufactured.

What salt mix are you using and have you measured it?

I know you don't believe it, but I guarantee that your tank is not consuming 50 ppm per day. There is no chemical mechanism that allows that much decline.

I am indeed running auto W/C and I'm using FRITZ Reef Pro MIX. I've been slowly switching to Red Sea Coral Pro to see it it helps. For now I can see that mag is low because Coraline Algea growth has slowed. When the levels come up so does the growth rate and the corals look much better with better polyp extension.

 

[gizmodo]

50 ml of a 460 g/L solution of Seachem Reef Advantage magnesium contains 23 g of product. That much is claimed by Seachem to raise magnesium by 23 ppm in 20 gallons of water.

I expect you have a magnesium testing issue, not least of which is the initial reading at 800 ppm. Magnesium just doesn't get that low, unless you are doing water changes with a mix that is grossly mismanufactured.

What salt mix are you using and have you measured it?

I know you don't believe it, but I guarantee that your tank is not consuming 50 ppm per day. There is no chemical mechanism that allows that much decline.

I understand you are frustrated with me for not grasping what should be very basic concepts. You are also an expert in your field but this is very real. My LFS, my father (with over 20 years of reefing experience) myself and even my girlfriend have all EXACTLY EXACTLY EXACTLY THE SAME RESULTS WITHIN MARGIN OF ERROR. The low initial magnesium was due to a previous crash brought on by a heater failure. The tank sat for months. I don't want to believe it either but unfortunately I'm stuck. I tried, red sea, salifert, auquaforest and all within margin of error. I'm waiting for ICP tests to come back in stock in my area to be absolutely sure. I can assure you this is not a testing issue but a very very severe chemistry issue. I'll go pick up a Hannah checker for magnesium to have one other data point to confirm that this unbelievable phenomenon is really happening. I am pleading with you. What is more likely? 30 tests across 4 people with 3 brands(2 purchased within the last 3 months) are wrong or there is something severly wrong with my tank. I've been testing water for 8 years and I tried everything to prove that I was wrong. I want to think I'm wrong. As you said, it can't be possible. But right now this is what I've got. I'd send you a water sample if I could

 

[TokenReefer]

Have you double and triple checked your salinity with calibrated devices? That's what I'd be focusing on personally especially since the only way this would be possible as Randy stated is changes in salinity... But what do I know lol. Watching this one

 

[bxclent]

I understand you are frustrated with me for not grasping what should be very basic concepts. You are also an expert in your field but this is very real. My LFS, my father (with over 20 years of reefing experience) myself and even my girlfriend have all EXACTLY EXACTLY EXACTLY THE SAME RESULTS WITHIN MARGIN OF ERROR. The low initial magnesium was due to a previous crash brought on by a heater failure. The tank sat for months. I don't want to believe it either but unfortunately I'm stuck. I tried, red sea, salifert, auquaforest and all within margin of error. I'm waiting for ICP tests to come back in stock in my area to be absolutely sure. I can assure you this is not a testing issue but a very very severe chemistry issue. I'll go pick up a Hannah checker for magnesium to have one other data point to confirm that this unbelievable phenomenon is really happening. I am pleading with you. What is more likely? 30 tests across 4 people with 3 brands(2 purchased within the last 3 months) are wrong or there is something severly wrong with my tank. I've been testing water for 8 years and I tried everything to prove that I was wrong. I want to think I'm wrong. As you said, it can't be possible. But right now this is what I've got. I'd send you a water sample if I could

I'll be curious to see what the Hannah checker says

 

[Randy Holmes-Farley]

First step is to use that same magnesium kit on new salt water of the same brand you are using.

Second is to double check the salinity with a different tool.

At fixed salinity, magnesium cannot decline to 800 ppm even in a tank sitting fallow for decades unless you add many hundreds of dKH of alk to it. It has nowhere to go.

 

[I never finish anythi]

So salinity, or the salt batch must be the issue?? What else could it be ?? Watching

 

[gizmodo]

Have you double and triple checked your salinity with calibrated devices? That's what I'd be focusing on personally especially since the only way this would be possible as Randy stated is changes in salinity... But what do I know lol. Watching this one

I'm going to calibrate all of my refractometers tonight. My LFS has a digital Hannah salinity checker. I'll bring a water sample there to be sure I'm not the issue.

 

[gizmodo]

First step is to use that same magnesium kit on new salt water of the same brand you are using.

Second is to double check the salinity with a different tool.

At fixed salinity, magnesium cannot decline to 800 ppm even in a tank sitting fallow for decades unless you add many hundreds of dKH of alk to it. It has nowhere to go.

I'll test the salt batch with all of the test kits
It's a long story but every metric was low and took me the better part of a year to get everything back up with giant swings. Alk, Calc were awfully low. Had some family stuff come up and I got lazy.

I will double check with another tool. Lfs has a Hannah checker for salinity.

 

[gizmodo]

So salinity, or the salt batch must be the issue?? What else could it be ?? Watching

It was my first thought so I bought another batch but no difference. So I'm switching brands to see it that helps

 

[kevgib67]

My curiosity is peaked, following.

 

[ryanjohn1]

Personally I know my Hanna salinity checker is sketchy. I use that and a refractor

 

[gizmodo]

Just re-calibrated my equipment. One refractometer was 1 point off the other was dead on. Current salt mix for the auto WC with the same test kit is reporting 1500ppm+ Mg (46PPT)
Tank is 1050 (37PPT)
Looks like I've just found that I have an evaporation issue. Still doesn't explain low Mg. I give up.

 

[gizmodo]

Personally I know my Hanna salinity checker is sketchy. I use that and a refractor

I recalibrated my refractometer. I always have fresh calibration solution on hand. I'm going to try the Hanna at my lfs tomorrow.