Maintaining Magnesium Levels

[Vader]

I was just wondering if anyone else's tanks goes through (or absorbs) more magnesium than other additive like Calcium and Alkalinity. My tank is not heavily stock by any means, mostly soft coral, and every time I take readings, I'm adding way more Mag. than anything else.

[ctenophore]

It shouldn't drop like that. Ca:Mg ratios are typically 100:1, possibly as low as 25:1 in some types of calcareous algae. You may want to try a different test kit.

[Grav]

I second that. Some MG test kits are total junk. Try testing new saltwater, super over dose it (do the math and estimate what the change should be, and then test again.

 

MG is in very high levels compared to others (1200-1300ppm vrs 400 for CA) and consumption is far lower as noted... so unless you are very sure of your test kit and/or are seeing indicators (like loss of color in SPSs) don't over react / over dose.

[Mich]

I've had this problem in the past as a result of growing chaeto as a nutrient exporter and adding two part calcium and Kalk, as well as weekly iodine strontium magnesium, trace elements... topping off but not doing water changes. Most magnesium additives won't significantly raise the levels in the tank as it's depleted compared to everything else. It should be three times the level of your calcium and most mineral additives don't contain enough magnesium to keep the ratio as high as it is in newly mixed saltwater. The one additive that does seem to work is the one that's like pure granular epsom salts, you have dissolve it in a seperate container and pour the solution in. Be prepared to add a lot in several doses check your calcium, alkalinity, and ph as you go. If your mag is already below 1000 it's probably easier just to replace it by mixing new saltwater.

 

In my experience salifert is the most reliable test kit.

[Vader]

I second that. Some MG test kits are total junk. Try testing new saltwater, super over dose it (do the math and estimate what the change should be, and then test again.

 

MG is in very high levels compared to others (1200-1300ppm vrs 400 for CA) and consumption is far lower as noted... so unless you are very sure of your test kit and/or are seeing indicators (like loss of color in SPSs) don't over react / over dose.

 

I'm using Salifert for testing Mag. Thanks for the advice everyone. I take it slow with my system as far as adding live stock and the tank is still in it's eary stages. Started up in late December. I'm not worried about the rate that I'm going through Mag, it's was just something I noticed while keeping track of my parameters and dosing. Since I'm so new to this hobby, I was just wondering if anyone else's tanks go through more Mag as well. But as far as my water, I take readings about a day or two after a water change, which is done every month.

[CHUBAKAH]

From what everyone I have ever heard from who used a Salifert test kits at one point or another, they are JUNK. Take a water sample with you next time you go to a local fish store, and have them test your water to compare. Dave, who we installed the HVAC system for just last week had his water tested at AQUACO because his water kept testing very low with a Sallifert kit, and he had lost like 10 colonies. Turns out his Mag was off the chart and over 2000.

[Vader]

From what everyone I have ever heard from who used a Salifert test kits at one point or another, they are JUNK. Take a water sample with you next time you go to a local fish store, and have them test your water to compare. Dave, who we installed the HVAC system for just last week had his water tested at AQUACO because his water kept testing very low with a Sallifert kit, and he had lost like 10 colonies. Turns out his Mag was off the chart and over 2000.

 

 

What brand of Mag. test does he use?

[Almon]

From what everyone I have ever heard from who used a Salifert test kits at one point or another, they are JUNK. Take a water sample with you next time you go to a local fish store, and have them test your water to compare. Dave, who we installed the HVAC system for just last week had his water tested at AQUACO because his water kept testing very low with a Sallifert kit, and he had lost like 10 colonies. Turns out his Mag was off the chart and over 2000.

Salifert makes excellent test kits. I've had very positive experiences with them.

 

Any test kit can be compromised to the point that it is inaccurate and it's almost always due to the consumer, whether it's been stored improperly or is three (3) years old, or whatever. I also agree that your test kit is suspect, but not because it was manufactured by Salifert.

 

I don't notice the need to add more Mag Supplements over calcium or Alkalinity supplements. It seems that I need more Calcium and Carbonate additives than Magnesium.

 

You may also wnat to consider the possibility that your Mag supplement is not as efficient as you think. It may not be adding the amount of Mag that you think it is.

[ctenophore]

Salifert has been a brand I have used for a long time, maybe 10 years now?

 

The best kits come with a standardized reference solution. I know Salifert's Alk kits do, not sure about their newer mag kits.

 

FWIW, I use the Tropic Marin Ca/Mg combo kit because I got one cheap. I also use a Salifert Ca & mg kit but they seem to be within 5% agreement so I prefer the TM kit since it tests both at once. When it runs out I will go back to Salifert.

[CHUBAKAH]

Salifert makes excellent test kits. I've had very positive experiences with them.

Congratulation on being the first person I have ever heard anything positive about Salifert test kits from.

 

What brand of Mag. test does he use?

TBH the brand name escaped me at the moment. It's a commercial brand, and he backs that test up with TM.