Where's your Mg at?

[Azedenkae]

As per title. I read that elevated Mg levels (not too high) can indirectly support coral growth (especially stony corals) as it helps prevent abiotic precipitation of calcium and carbonate and thus promotes better biotic calcium carbonate sequestration. This article in particular suggests having Mg at 1,300 to 1,400ppm: https://rucore.libraries.rutgers.edu/rutgers-lib/47921/PDF/1/

So my question is, where are your Mg levels at, and how are your SPS growing?

 

[jda]

No idea. My acropora grow well. This is not flippant, but I never found it to matter much, but my salt mix has a good level at about 1320 and I have a CaRx that adds in in balance. I would probably never test it unless I dosed it independently of other things, like a 3-part system.

 

[Azedenkae]

No idea. My acropora grow well. This is not flippant, but I never found it to matter much, but my salt mix has a good level at about 1320 and I have a CaRx that adds in in balance. I would probably never test it unless I dosed it independently of other things, like a 3-part system.

No that's fair. I guess Mg should not be heavily consumed (if at all), so it's not as important to measure. Though I guess, follow up question. What is your calcium and dKH values? Say when you do a water change or when you are dosing or your target values, whatever is highest?

 

[jda]

Mag does get consumed. You have to add it back. However, if you add it in balance, then you don't really have to test for it. I have a calcium reactor.

I keep my alk around 7.0 and calcium at 425ish. I use IO and I have to add acid to the mix to lower the alk and also use calcium chloride (driveway melt) to raise the calcium.

 

[Gtinnel]

My magnesium stays at 1400 consistently and so far I haven't had to dose any, although I've only had stony corals in this tank for about 6 months or so and most of them are frags beside a few large colonies. I'd say most of them are growing quickly but I don't really have anything to compare their growth to.

 

[LDog74]

Mg @ 1250

 

[Try'nNotToKillStuff]

I generally try to have my Mag about 3x my calcium. And I agree with JDA that Mag does get consumed. I have a Neptune Trident that tests Mag twice a day. I am not sure why, but occasionally it drops for no apparent reason. Then I dose it manually.

 

[monkeyCmonkeyDo]

? Idk never tested it. Lol
D

 

[Rmckoy]

Alk 7.5 dkh ( 134ppm )
Cal 425
Mag 1300
Mostly sps . , everything is growing

 

[homer1475]

ALk 7.0
CAl 420
MAG 1350

Mixed reef mostly SPS. I rarely add any MAG as my salt mix is fairly high(IO), and with weekly WC's, it keeps it right around 1350.

FWIW.....
We used to purposely raise MAG to over 1600 with a specific MAG product to combat bryopsis. No one ever had problems with MAG in those ranges.

 

[Spieg]

Values fluctuate some but typically stay around;
dKH = 8.5
Ca = 440
Mg = 1400
Stony coral growth has been pretty good.

 

[redeyejedi]

Mixed reef

Alk= 8.3 - 8.6
Cal= 500ish
Mag=1500

 

[BaysEndReef]

Mixed Reef

dKH=8.25
Ca=465
Mg=1483

Tested with Trident.