Zero Ca and Mg in Tank

[Saurabhdxb]

Hi guys i hv been running a 30g and 20g tanks for few months with corals in both, but it seems my corals started to die off specially the hammers n torches, on testing the parameters i noticed tht my CA and MG were Zero infact negative, i started to dose both Ca and Mg twice daily, but its been two week and i see no change in the parameters increase, i am dosing the Redsea Foundation Ca and Mg, i also changed by Salt to Redsea Coral Pro, but i am unable to identify the problem, need your support n guideance to get the parameters to the correct levels

 

[redfishbluefish]

First off, welcome to R2R! #WelcometoR2R

What test kits are you using? It's impossible that Calcium and Magnesium are zero.

And stop dosing until we can get this figured out.

 

[Saurabhdxb]

I hv been using the Salifert test Kit, for all the three testing of KH, Ca and Mg and API kit for the other parameters

 

[redfishbluefish]

I would suggest reviewing these videos to make sure you're using the kits correctly. Something is not right!

 

[Saurabhdxb]

i hv been doing exactly as in the video, i also had an expert from my LFS to check test the water n tht when he asked me to start dosing, i plan to change the test kit and hv the test done with Red sea foundation pro kit.

 

[redfishbluefish]

Just so you know, the least "fortified" salts that I'm aware of, made to 1.026 SG, would have magnesium in the 1280 ppm range, and calcium in the 370 ppm range. And comparing the three, Alk, Calc and Mag, alk is the one you would see dropping the fastest.....magnesium the least. With water changes, I very rarely dose magnesium.

Good suggestion in trying new kits.....or have your LFS test your water.

 

[BarSnackz]

There is no way that your Ca and Mg are zero. I also have a feeling that there is a deeper problem to your corals dying than your nutrient levels. Try a different testing kit

 

[tehmadreefer]

It’s absolutely impossible to have zero or “negative” ca and mg. It’s the test kits or they are being used incorrectly.

 

[tehmadreefer]

Just curious how does a test even show a negative value? that is impossible in itself.

 

[piranhaman00]

Just curious how does a test even show a negative value? that is impossible in itself.

The titration changed colors before the drop even hit the sample! Minus 0.1mL

Like others said, quit dosing!

 

[Saurabhdxb]

Dear All, i hv just had an expert from LFS and changed 80% water in both my tanks, used red sea coral pro salt, he got some water from the shop to test if my selifert test kit was working correctly, and it did give the correct readings for the water from the LFS, after the water change in my tank we teated the water again and it still says zero, i had to fill the syringe twice to get the color change for both Ca and Mg, my Kh is 9 in the tanks, i really surprised whts causing the Ca and Mg to be zero in the tank

 

[redfishbluefish]

Hold on! You used two syringes to get a color change....that's over 1000ppm!

With Salifert, they have a table where you look up the exact number you used on the syringe. As an example, for Calcium, if I started at 1.0mls, and now, after the color change, it says 0.18 at the bottom of the black plunger (I've used 0.82 of the syringe solution), but looking at the table, 0.18 = 410 ppm.

If I've used one entire syringe....syringe is at 0.0.....that's 500 ppm. When I go to the second syringe, it's now whatever I get with the second syringe PLUS the 500 ppm from the first.

Here's part of that table I'm talking about that you need to look at to get your numbers:

 

[Saurabhdxb]

same for the mg

 

[Saurabhdxb]

let me do a test again tomorrow and share few pic of the numbers i get

 

[redfishbluefish]

Yes, same for the Magnesium. Here's the magnesium table:

 

[Saurabhdxb]

i agree to what you mentioned, but for zero is without any color change, for the water to change the color it takes mk around 2 syringe. does it mean tht if the color does not change my Ca is at 500ppm

 

[redfishbluefish]

One complete syringe (for Calcium) is 500 ppm. If I need to start a second syringe, I continue to add that second syringe until I get the color change. Then I take the reading for that syringe (let's say 0.22, which equals, from the table, 390ppm) and add the two together....500 + 390 = 890ppm.

Hope this helps.

 

[reef lover]

Welcome to r2r!

 

[Saurabhdxb]

i agree to what you mentioned, but for zero is without any color change, for the water to change the color it takes mk around 2 syringe. does it mean tht if the color does not change my Ca is at 500ppm

i get you now, that means i shud not be running behind the color change rather to get the Ca and Mg down to a acceptable level, may be that is why the Kh has been stagnant at 9

 

[Smarkow]

i get you now, that means i shud not be running behind the color change rather to get the Ca and Mg down to a acceptable level, may be that is why the Kh has been stagnant at 9

Do you have a lot of white precipitant in the tank which is new? I would think that if your Ca was 1k+, even with high Mg, and you kept dosing that there should be some precipitant.