Magnesium level not raising

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Couple of questions.

I am having issues getting my magnesium levels up to the 1300 range. Ph runs about 8.3. Im using tropic marin pro reef. I've also used a whole bottle of fritz magnesium. Any suggestions as to if the cloudy tank could be calcium precipitation?

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Have you tested magnesium with another kit? I’f so. It could take quite a lot of magnesium supplement to get it 400 points up. You could use epsom salt, but that will also raise sulfur, you can also just do large water changes.
 
Have you tested magnesium with another kit? I’f so. It could take quite a lot of magnesium supplement to get it 400 points up. You could use epsom salt, but that will also raise sulfur, you can just do large water changes.
I verified with my api kit.
 
I use Fritz RPM salt, my tank water was constantly reading low. I read the box which said that the salt should mix to 1350. I mixed up a fresh batch of saltwater and sure enough it read 1350 ( I use Salifert test kits ). I bumped it up with Fritz magnesium and then began dosing All for Reef. I occasionally have to dose some magnesium, maybe once month. I suggest you mix up a fresh batch of saltwater and test it. Compare it to what your salt says it should mix to. If it’s off either you got a bad batch of salt or you’re having testing errors.
 
Try the kit on some new salt water, Actually getting magnesium that low takes a ton of alk additions with no magnesium, or very low salinity. Test error is most likely, even with 2 tests. Testing is so bad I neither do it nor recommend it.
 
Try the kit on some new salt water, Actually getting magnesium that low takes a ton of alk additions with no magnesium, or very low salinity. Test error is most likely, even with 2 tests. Testing is so bad I neither do it nor recommend it.
Will do. I suspected that it may be the case of just testing bad so I used the calibration fluid for the trident and it was spot on with the fluid measurements. I do dose all for reef and a little extra cal from fritz. The mag im currently using is redsea. I havent set my dosing pumps up because I have not been able to stabilize and want to get closer to the 1350 mag / 420 cal/ 9 alk before i set up to doese. My calculations show im going to need a half liter of mag to get to the right levels.
 
Poor test results or low salinity. Chances it is actually low magnesium is slim to none
35ppt on the salinity using calibrated refractometer .

Same trident reagents with the calibration fluid.

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Im using pro-reef salt from tropic marin. Im going to do a 40 gal water change this evening and see if it helps.
 
In all the many many threads of people seeking help with very low magnesium, I cannot think of one that was not salinity and/or test error. It might have happened but I can’t think of one. People really do not like the idea that their kits or trident are giving erroneous Magnesium numbers, I get it.

Magnesium test error so common that Randy has recommended not bothering to test it and just dose in a ratio of calcium doses. That has served many of us well. ICP has shown magnesium in my tank in a good range for a couple of years now with that method.

testing fresh mixed salt water is an ok way to validate the trident. Let’s know what you find. If it comes up low, don’t fall down the rabbit hole thinking your salt mix is bad. It’s the test. Best of luck.
 
In all the many many threads of people seeking help with very low magnesium, I cannot think of one that was not salinity and/or test error. It might have happened but I can’t think of one. People really do not like the idea that their kits or trident are giving erroneous Magnesium numbers, I get it.

Magnesium test error so common that Randy has recommended not bothering to test it and just dose in a ratio of calcium doses. That has served many of us well. ICP has shown magnesium in my tank in a good range for a couple of years now with that method.

testing fresh mixed salt water is an ok way to validate the trident. Let’s know what you find. If it comes up low, don’t fall down the rabbit hole thinking your salt mix is bad. It’s the test. Best of luck.
Thanks. It doesnt seem to be causing issues but just for my anxiety. I havent bought anything other than some zoas.
 
Update. I have a young son that is very big on doing what daddy does. I caught him adjusting my refractometer to the tune of + 3 ppt off. I checked it and it didnt read zero. So i zeroed it and then found that my water was at 32 ppt instead of 35. I fear this is the cause because as i raise the salinity my mag and cal is raising to where it should be. Problem is i thpught i had ich on my tangs but now i fear it was the salinity that was more to blame. Could the low salinity be the cause or everything?
 
Update. I have a young son that is very big on doing what daddy does. I caught him adjusting my refractometer to the tune of + 3 ppt off. I checked it and it didnt read zero. So i zeroed it and then found that my water was at 32 ppt instead of 35. I fear this is the cause because as i raise the salinity my mag and cal is raising to where it should be. Problem is i thpught i had ich on my tangs but now i fear it was the salinity that was more to blame. Could the low salinity be the cause or everything?

If tank water is at 32 ppt instead of 35 ppt, everything (except ooh and ORP) will be about 9% lower. Instead of 1300 ppm for magnesium, it would be 1189 ppm.
 
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So these levels are pretty accurate. Im currently topping off with 35 ppt so hopefully I'll get the levels up soon.
 
Update. I have a young son that is very big on doing what daddy does. I caught him adjusting my refractometer to the tune of + 3 ppt off. I checked it and it didnt read zero. So i zeroed it and then found that my water was at 32 ppt instead of 35. I fear this is the cause because as i raise the salinity my mag and cal is raising to where it should be. Problem is i thpught i had ich on my tangs but now i fear it was the salinity that was more to blame. Could the low salinity be the cause or everything?

Is the refractometer designed for sea water?

You should be calibrating using a 1.026 refractometer calibration solution, not RODI water.
 
Update. I have a young son that is very big on doing what daddy does. I caught him adjusting my refractometer to the tune of + 3 ppt off. I checked it and it didnt read zero. So i zeroed it and then found that my water was at 32 ppt instead of 35. I fear this is the cause because as i raise the salinity my mag and cal is raising to where it should be. Problem is i thpught i had ich on my tangs but now i fear it was the salinity that was more to blame. Could the low salinity be the cause or everything?

Is the refractometer designed for sea water?

You should be calibrating using a 1.026 refractometer calibration solution, not RODI water.
The refractometer is the one from bulk reef supply. The calibration fluid I bought from the lfs is 0ppt. I didnt fond 35 ppt. But honestly isnt calibrating to anything ok as long as its a known level? Be it 35, 70, or 0.
 
The refractometer is the one from bulk reef supply. The calibration fluid I bought from the lfs is 0ppt. I didnt fond 35 ppt. But honestly isnt calibrating to anything ok as long as its a known level? Be it 35, 70, or 0.
No, salt water and sea water do not have the same refractive index.

I don't know which unit you have from BRS.

If the refractometer you have purchased is designed for salt water (not seawater), you need to calibrate with a 1.026 calibration solution. I believe BRS state that in their instructions.

If you have the Milwaukee unit, then it is a seawater device that can be calibrated with distilled water.

BTW, A 0 ppt calibration solution is simply distilled water
 
This is the one I have. Mine didn't have calibration fluid with it though. So i found some at the store either in Nashville or Atlanta. I go to both often.
https://www.bulkreefsupply.com/refr...=11040&indexName=brs_prod_m2_default_products
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That model should be calibrated with a 1.026 calibration fluid.

If you have accurate scales you can make your own using table salt and the instructions below.

There are 3 recipes - be sure to use the one for refractometers.

https://www.reef2reef.com/ams/reef-aquarium-salinity-diy-calibration-standards.956/
 

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