Magnesium usage

[Jrod381]

Hello R2R, I have connected my doser it’s been running for about a month or so. I have 310 display total 380 volume. Alk seems to be for the most part pretty stable from 8.4-8.9. Cal has been fluctuating but I feel it’s the test but I notice one day I’m using only 25ppm the next day it can be 75ppm cal has been fluctuating from 365 - to 435ppm.


What has me really stumped is my magnesium I cannot get it up no matter what I try. The highest have been able to get it is at 1150.

Now I don’t have many corals in the tank and unfortunately lost a lot recently when the temp in the tank shot through the roof when my ac went out.

I’m dosing AF components. And this what I’m dosing daily and it just doesn’t seem right. Also doing 3gal daily water changes

CA- 100ml
ALK- 80ml
MAG-100ml

These are my current parameters
Ca-375
Alk-8.9dkh
Mag-1050ppm
Pho’s-0.06ppm
No3-25ppm
Ph-7.86
Temp-76.6
many help is greatly appreciated

 

[Uncle99]

Could the test be wrong?

 

[Jrod381]

Could the test be wrong?

honestly I have thought the same ive been using both salifert and Hanna test. For the mag I only have a salifert test but it’s the second one and both are pretty much showing the same numbers.

I’m planning on getting a trident to test for me if I see it becomes consistent if not I plan on getting a mastertronic when released

 

[Uncle99]

Or just test the test.
Take a cup of RODI
Add Some Mg, test, add, test, etc, to see if you can get it passed 1150.
If it does go passed 1150, keep raising DT.
I remember when I first raised my MG, it felt like a lot to get it to 1365, but, it finally did.
Salifert is a really easy and fast test so it should be much work.

 

[redfishbluefish]

Stop dosing magnesium.....something is not right. What salt are you using and what is the magnesium content of that salt. Please make a fresh batch of saltwater and test that water for magnesium. I think you're have testing issues....old kits, user error...something.

 

[jcorndogg]

I had the exact same issue. Would hover between 1150-1250. Could never get to the 1300’s. I bought a new salifert test kit and 3 brands of mg supplement..... aquavitro, aquaforest and brightwell. It would just precipitate out and caused an algae bloom.

Worried that my mg was 2000+, I stopped dosing completely. Then I read on an old forum that using the cheaper mg supplement helped a guy in the same boat. So, I bought some $5 Kent magnesium from amazon and it worked. I even bought an aqua forest mg test as an additional verification.
My next step was BRS sells magnesium chloride and magnesium sulfate. One product they recommended for adjustments, the other for maintenance.

 

[Mastiffsrule]

Evening

One thing about Mg I think a lot of people underestimate of how much is needed to make it move. It is not like Ca or Alk.

I ran this real quick . Not sure if the right product. I would dose slowly to get to the target. Once there maintaining is easier

 

[Jrod381]

I’m using IO salt and I have never had this kind of issue in any of my tanks. I actually started dosing by hand fluval. Magnesium in conjunction with the AF and that’s when I got it up to 1150.

I just read somewhere that carbon dosing can affect magnesium levels, I’m wondering if that’s what’s happening in my tank

 

[Nick Steele]

Magnesium takes a lot to raise. In my 20g I had to add 80ml to get my tank from 1100-1350 (Brightwell’s liquid I use). I didn’t mix my salt mix up so some stuff settled out and I had low mag with super high alk. I started mixing the boxes and now I get 1350 mag with 8 alk right where it should be. Test your new salt water and see if that is running low mag.

 

[NanJ]

We have a 300 g DT and use Aqua Vitro Ions (by Seachem) as a magnesium supplement. On the label it specifies how much product to use per gallon to raise the magnesium by 5 mg/L. I did the calculations on our tank and needed something like 700 ml to raise the magnesium to 1380. Of course the product can’t be added all at one time so it took several weeks to raise the magnesium level.

 

[Randy Holmes-Farley]

I just read somewhere that carbon dosing can affect magnesium levels, I’m wondering if that’s what’s happening in my tank

No, that's not true.

 

[Randy Holmes-Farley]

We have a 300 g DT and use Aqua Vitro Ions (by Seachem) as a magnesium supplement. On the label it specifies how much product to use per gallon to raise the magnesium by 5 mg/L. I did the calculations on our tank and needed something like 700 ml to raise the magnesium to 1380. Of course the product can’t be added all at one time so it took several weeks to raise the magnesium level.

No magnesium supplements needs to be added that slowly. Raising magnesium 25 ppm per day is typically fine.

 

[Randy Holmes-Farley]

Hello R2R, I have connected my doser it’s been running for about a month or so. I have 310 display total 380 volume. Alk seems to be for the most part pretty stable from 8.4-8.9. Cal has been fluctuating but I feel it’s the test but I notice one day I’m using only 25ppm the next day it can be 75ppm cal has been fluctuating from 365 - to 435ppm.


What has me really stumped is my magnesium I cannot get it up no matter what I try. The highest have been able to get it is at 1150.

Now I don’t have many corals in the tank and unfortunately lost a lot recently when the temp in the tank shot through the roof when my ac went out.

I’m dosing AF components. And this what I’m dosing daily and it just doesn’t seem right. Also doing 3gal daily water changes

CA- 100ml
ALK- 80ml
MAG-100ml

These are my current parameters
Ca-375
Alk-8.9dkh
Mag-1050ppm
Pho’s-0.06ppm
No3-25ppm
Ph-7.86
Temp-76.6
many help is greatly appreciated

Real magnesium consumption is very low, like 1 ppm per day. It is not more than about 1/10th of the calcium consumption. Anything substantially larger is testing error of some sort.

it does take a huge amount of magnesium additive to boost it. Even solid magnesium supplements are only about 10% by weight magnesium and a decent sized tank has pounds of magnesium in it.

 

[Jrod381]

So I just tested the water in my mixing station and mag is at 1290 according to IO website they label their parameters at 1320 for mag

i just tested my tank directly and it read at 1110

 

[Dkeller_nc]

To reinforce the calculation that Mastiffsrule provided, I looked up the Aquaforest magnesium supplement mixing directions, and it says to mix 10g of the supplement in 1 liter of water. That means that to raise your mag level from 1150 to 1200 ppm, you'd need to add about 60 liters of the AF supplement when mixed according to directions to your system.

I am not sure why AF would have you make such a weak solution - perhaps its because they suggest that you make a combined Calcium & Magnesium solution, and they've calculated a ratio based on the assumed ratio of Ca and Mg that stony corals consume.

In contrast, I calculated the amount of the BRS MgCl2/MgSO4 mix to raise the mag in your system from 1150 to 1200 ppm - total of 1.5 liters. So for the purposes of adjusting your system to your desired baseline, you might want to consider either purchasing the BRS mag mix and using it according to directions, or make the AF mag supplement by itself without the suggested calcium component at 10X the concentration of the package directions.

 

[Nick Steele]

Correct me if I’m wrong everyone but for your course of action I would raise your water change mag level to around 2000 mag and do 10% water changes until you to where you’d like to be. That will raise your mag about 100 per water change.

You could does every day if you want but I’m always skeptical about adding things directly to the display.

 

[Jrod381]

Alright so I told myself something just isn’t adding up. So I decided to take some sample water to WWC. Now here I am testing everyday like a madman alk, mag, ca, pho’s and nitrate. Well it was as simple as testing one thing to find the problem and wwc made that the first test without me telling them anything they tested salinity which I had not done. 1.021

Then I said how can it be so low I have my ato and water level is always the same then dawned on me if you remember when I said I lost half the coral to my temp spike. Well to cool the tank off I had to do one thing quickly you guessed it bags of ice well I never shutoff my ato and ice melted in the sump. That explains why my salinity is so low and magnesium as well since it takes much mote to increase levels as suppose to ca and alk.

now i have some work to do with my mixing station to help slowly raise my salt level and also my mag level, smh

 

[Randy Holmes-Farley]

I am not sure why AF would have you make such a weak solution - perhaps its because they suggest that you make a combined Calcium & Magnesium solution, and they've calculated a ratio based on the assumed ratio of Ca and Mg that stony corals consume.

It's because they recommend 1:1:1 dosing.

 

[Dkeller_nc]

Actually, don't raise your specific gravity by attempting to make concentrated saltwater in your mixing station. That is very, very likely to result in a large amount of precipitation of calcium carbonate in your mixing station which will foul your mixing equipment and a diminished calcium and alkalinity concentration per unit salt content, which will then result in a diminished Ca and Alk in your tank water, increased dosing of supplements based on your test results, or both.

Instead, simply add a bucket of normal specific gravity saltwater to your sump everyday. Your ATO will shut off, evaporation will lower the water level and also concentrate the dissolved solids in your tank water, and the ATO will take back over once the level drops again. Within a few days, you'll be back to normal specific gravity, easy peasy.

 

[Dkeller_nc]

Another comment that might help you make your reef disaster resistant. In addition to the usual back-up equipment like extra pumps, heaters, salt, always keeping 50 gallons of RODI on hand, etc.., you might want to consider a small generator, and a small plug-in window air conditioner. The little camping generators that are available from the B.O.R.G. (big orange retail giant) cost about $450. A far more reliable and quiet version is available from Honda. Either way, they've saved my tanks on multiple occasions. Ditto for the window AC - cost me $150, is small and light enough to hoist into a window with little trouble,