Problem raising magnesium.

SaltwaterGuruNeeded · Jul 10, 2021

I can't seem to raise magnesium, I am worried that if I put anymore in that maybe the levels will come up overnight for some reason? Pls help not sure if I am wasting my 2 part magnesium mix. My levels at the start of the day was 1140 magnesium, it is now at 1185. Can't seem to get it to 1200.

blasterman · Jul 10, 2021

How big is your tank. I assume the bag is just magnesium chloride.

Not sure what a 2part magnesium mix is.

SaltwaterGuruNeeded · Jul 10, 2021

blasterman said:
How big is your tank. I assume the bag is just magnesium chloride.

Not sure what a 2part magnesium mix is.

Has both MgS and MgCl and the tank is 125g with 75-85 lbs of rock. And about a 1.5" sandbed.

Randy Holmes-Farley · Jul 11, 2021

Did you use the calculator to know how much to add? Use the entry for Randy's recipe.

FWIW, magnesium that low is most often from low salinity and can be fixed by raising it 9assuming it is not the most common issue test error).

Reef Chemistry Calculator

SaltwaterGuruNeeded · Jul 11, 2021

Randy Holmes-Farley said:
Did you use the calculator to know how much to add? Use the entry for Randy's recipe.

FWIW, magnesium that low is most often from low salinity and can be fixed by raising it 9assuming it is not the most common issue test error).

Reef Chemistry Calculator

My salinity is 1.024 and used a calibrated refractometer.

Uncle99 · Jul 11, 2021

Mine took a lot of product to get it to 1400ppm, but once there, was easy to keep there.

If your confident in your test results, keep pushing it forward.

Randy Holmes-Farley · Jul 11, 2021

SaltwaterGuruNeeded said:
My salinity is 1.024 and used a calibrated refractometer.

That's a big part of the problem then.

The expected value for magnesium in seawater at that low salinity is only 1164 ppm.

Raise that to 35 ppt (sg = 1.0264) and magnesium will rise by over 100 ppm.

Uncle99 · Jul 11, 2021

I always test and adjust MG first, before doing any other testing or adjusting of CA and Alk, otherwise, you may get odd test results.

SaltwaterGuruNeeded · Jul 11, 2021

Randy Holmes-Farley said:
That's a big part of the problem then.

The expected value for magnesium in seawater at that low salinity is only 1164 ppm.

Raise that to 35 ppt (sg = 1.0264) and magnesium will rise by over 100 ppm.

But clownfish salinity isn't supposed to be in that range.

homer1475 · Jul 11, 2021

According to the reef calc, assuming displacement of sand and rock, I extimated you at 100G total water volume(just a guess).

It would take 524ml to go from 1185 to 1250.

It takes quite a bit of mag to raise levels.

Randy Holmes-Farley · Jul 11, 2021

SaltwaterGuruNeeded said:
But clownfish salinity isn't supposed to be in that range.

OMG, tell all those clownfish in the ocean to run for their lives!!!!!

Sarcasm aside, whatever you heard about clowns needing low salinity is not correct. The ocean is, on average, 35 ppt, and there's no reason to target anything else in a reef tank.

SaltwaterGuruNeeded · Jul 11, 2021

Randy Holmes-Farley said:
OMG, tell all those clownfish in the ocean to run for their lives!!!!!

Sarcasm aside, whatever you heard about clowns needing low salinity is not correct.

What about cerith Snails?

homer1475 · Jul 11, 2021

1.026 is normal average ocean salinity. Keeping your reef in that range will benefit everything including your MAG issue.

Randy Holmes-Farley · Jul 11, 2021

SaltwaterGuruNeeded said:
What about cerith Snails?

Unless you keep creatures from a brackish environment, there's no accepted rationale to target anything but 35 ppt, unless you are trying to match a supplier to cause less salinity change when you buy things.

SaltwaterGuruNeeded · Jul 11, 2021

homer1475 said:
1.026 is normal average ocean salinity. Keeping your reef in that range will benefit everything including your MAG issue.

Ok. I will try to raise it by not topping off and adding saltwater that is at 1.027

SaltwaterGuruNeeded · Jul 11, 2021

Randy Holmes-Farley said:
Unless you keep creatures from a brackish environment, there's no accepted rationale to target anything but 35 ppt, unless you are trying to match a supplier to cause less salinity change when you buy things.

Well, my clownfish came from Petco...they had ick and we're kept in a tank at around 1.018 or less. I acclimated the for 2hrs. And they were in the tank with 1.024 salinity. They ate as soon as they were introduced.

homer1475 · Jul 11, 2021

Topping off with 1.026 saltwater is the proper way to raise your salinity. Just keep an eye on it because with using an ATO, you can very easily overshoot.

I personally will just do my normal WC with higher salinity water. I have overshot using salt water in my ATOP before, simply because I forgot I had salt water in my ATO container.

homer1475 · Jul 11, 2021

SaltwaterGuruNeeded said:
Well, my clownfish came from Petco...they had ick and we're kept in a tank at around 1.018 or less. I acclimated the for 2hrs. And they were in the tank with 1.024 salinity. They ate as soon as they were introduced.

Vendors purposely keep fish in lower salinity water to save on salt costs, and to hinder diseases.

Fish can live in lower salinity water, your corals not so much.

SaltwaterGuruNeeded · Jul 11, 2021

homer1475 said:
Vendors purposely keep fish in lower salinity water to save on salt costs, and to hinder diseases.

Fish can live in lower salinity water, your corals not so much.

Funny you say that...they had an anemone in there...