Tropic Marin Magnesium?

gbroadbridge · Jan 27, 2025

Kenmx10 said:
I think the best thing to do is get a ICP test and see which numbers I can trust.

If you were to do that I'd store a bottle of tank water taken at the same time as the sample and keep that around as a reference for when you have future test irregularities.

Bear in mind though, that as long as Mg is above about 1200 or so the exact number is not really that important.

Reefer_Hommie · Jan 28, 2025

I used to use tropic Marin pro salt then I switched to tropic Marin’s symbiotic salt cus my n03 and Po4 were always a bit high switching to the symbiotic helped more than i expected it would I still run some GFO but the symbiotic salt is also high in alk,ca,mg and it costs a few buck more and doesn’t store very well I always use fresh made saltwater same or next day and with the regular pro by TM stores just fine if you like to store saltwater I’d keep that in mind and I also still dose TM’s all for reef to keep levels up but symbiotic dose test higher in all 3 main elements

If your not dosing already you could look into dosing tropic Marin’s all for reef and it should get your magnesium up.. hope this helps! Happy reefing everyone!!

rishma · Jan 28, 2025

I have a long history of fixating on a particular parameter and then measuring, experimenting, and measuring 3 more ways until I finally realize it didnt matter that much. That’s the path I think you are on @Kenmx10, and I don’t blame you one bit. Been there many times and I’ll be there again sometime soon I’m sure. The ICP test might be satisfying for you, because you’ll know the answer.

I suspect you’ll find the salts are in range per the manufacturer specs and your test kits are are incorrect. That’s my guess. It is pretty curious to have two kits reading so closely. This whole process may lead you RMM that many of use and feel pretty good about it.

Your ICP will also give you a salinity measurement which will give another assurance that your salinity measurement is good (or not, like me). I own a refracrimeter and a Milwaukee digital one like yours. I now only use the Tropic Marin hydrometer @Pod_01 posted.

Anyhow, good luck and let us know what you end up learning.

Randy Holmes-Farley · Jan 28, 2025

Kenmx10 said:
FWIW, I just mixed up a batch of Reef Crystals. Tested Mag using both Salifert test kits. They both read exactly the same. 1170 ppm. Seems, Either the salt is off or both test kits are off exactly the same amount. I calibrated my refractometer twice and took 2 sample readings . Both confirmed 1.026. The Digital Milwaukee confirmed the same. Odd that the magnesium tested low on both the Reef Crystals and the Tropic Marin Pro. It would be easier to blame the test kits if they weren't spot on with each other. Hard to believe both salts could be that far off though.

I expect it is more likely your kits or salinity is off than the salt mixes are lower than normal, but either is possible. I have little confidence in magnesium kits and think measuring it is often more trouble than it is worth.

How did you calibrate your refractometer?

Kenmx10 · Jan 28, 2025

Randy Holmes-Farley said:
I expect it is more likely your kits or salinity is off than the salt mixes are lower than normal, but either is possible. I have little confidence in magnesium kits and think measuring it is often more trouble than it is worth.

How did you calibrate your refractometer?

I bought 2 new bottles of calibration fluid to check my optical refractometer. Then tested my Milwaukee units against the optical meters and the solution. Being that the Milwaukee unit was consistently off by 0.001 I took it to the local fish store and had them test it as well and they confirmed the same thing.

ProvidenceTidalReef · Jan 28, 2025

Was the water tested before or after adding to the tank.? Are you cleaning your bucket before mixing? How long do you mix it for? What are your perms after mixing? If your alk, cal, PH are low then your mag will be low. I use this salt also after switching from fritz blue box and noticed lower testing numbers than specified on the box.

Kenmx10 · Jan 28, 2025

rishma said:
I have a long history of fixating on a particular parameter and then measuring, experimenting, and measuring 3 more ways until I finally realize it didnt matter that much. That’s the path I think you are on @Kenmx10, and I don’t blame you one bit. Been there many times and I’ll be there again sometime soon I’m sure. The ICP test might be satisfying for you, because you’ll know the answer.

I suspect you’ll find the salts are in range per the manufacturer specs and your test kits are are incorrect. That’s my guess. It is pretty curious to have two kits reading so closely. This whole process may lead you RMM that many of use and feel pretty good about it.

Your ICP will also give you a salinity measurement which will give another assurance that your salinity measurement is good (or not, like me). I own a refracrimeter and a Milwaukee digital one like yours. I now only use the Tropic Marin hydrometer @Pod_01 posted.

Anyhow, good luck and let us know what you end up learning.

Thanks, Im not trying to chase the numbers with the Magnesium. Im more concerned about which parameters are correct and incorrect. If it is the salinity then it will affect other parameters as well. If it is the magnesium, then I can just make adjustments to the water when doing water changes and not worry about it.

I suspect the salinity is low, like Randy stated, and question the accuracy of the calibration fluids. But when I test the Calcium and Alkalinity, they are higher than what the manufactures claim. Which brings me back to the Magnesium.

I remember way back in the day (maybe 15-20 years ago) the thought was that the magnesium was the most expensive ingredient in the salt and the manufacturers would skim on it at times to save money. I assume that's not the case and that our test kits were off.

The main reason for the ICP test, is to check the salinity and not the magnesium. If the salinity is off then I need to make the adjustments to correct it. Thx

Randy Holmes-Farley · Jan 28, 2025

Kenmx10 said:
I bought 2 new bottles of calibration fluid to check my optical refractometer. Then tested my Milwaukee units against the optical meters and the solution. Being that the Milwaukee unit was consistently off by 0.001 I took it to the local fish store and had them test it as well and they confirmed the same thing.

Bottles of what? Some commercial refractometer solutions are not very accurate.

But it certainly may be the mag kit.

rishma · Jan 28, 2025

Kenmx10 said:
Thanks, Im not trying to chase the numbers with the Magnesium. Im more concerned about which parameters are correct and incorrect. If it is the salinity then it will affect other parameters as well. If it is the magnesium, then I can just make adjustments to the water when doing water changes and not worry about it.

I suspect the salinity is low, like Randy stated, and question the accuracy of the calibration fluids. But when I test the Calcium and Alkalinity, they are higher than what the manufactures claim. Which brings me back to the Magnesium.

I remember way back in the day (maybe 15-20 years ago) the thought was that the magnesium was the most expensive ingredient in the salt and the manufacturers would skim on it at times to save money. I assume that's not the case and that our test kits were off.

The main reason for the ICP test, is to check the salinity and not the magnesium. If the salinity is off then I need to make the adjustments to correct it. Thx

You might know this already but you can buy the TM floating hydrometer which is considered quite accurate for less than the price of ICP.

gbroadbridge · Jan 28, 2025

Kenmx10 said:
The main reason for the ICP test, is to check the salinity and not the magnesium. If the salinity is off then I need to make the adjustments to correct it. Thx

The simplest way to check salinity is to make a DIY calibration solution using one of the recipes in this article.

https://www.reefkeeping.com/issues/2004-06/rhf/index.php
ICP does not directly measure salinity. Some vendors quote salinity but it is measured using a calibrated device, or calculated from the elements contained in the sample.

Kenmx10 · Jan 29, 2025

rishma said:
You might know this already but you can buy the TM floating hydrometer which is considered quite accurate for less than the price of ICP.

I think that's a good Idea. I think It will tell me what I need to know. Thank you.

Kenmx10 · Feb 16, 2025

If anyone is interested, I picked up the Tropic Marin Hydrometer. It confirmed what Randy suggested, that the calibration fluids where off. Salinity was reading 1.026 when it was really 1.025. Fortunately the Milwaukee Digital refractometer was in line with the TM hydrometer so that was good to know. Thx

KrAt0s · Feb 19, 2025

Kenmx10 said:
I think the best thing to do is get a ICP test and see which numbers I can trust.

following, did you ever get the ICP? I'm using pro reef and my mag is testing at 1370, so probably meets the claimed 1350 after factoring test tolerance. 2 buckets back to back testing the same.

Kenmx10 · Feb 19, 2025

KrAt0s said:
following, did you ever get the ICP? I'm using pro reef and my mag is testing at 1370, so probably meets the claimed 1350 after factoring test tolerance. 2 buckets back to back testing the same.

Not yet. What are you using to test your? Thx