Magnesium testing

[Aquattro]

Originally Posted by Johnny Reefer

... it is not necessary because I do not keep any SPS. Just LPS, softies and I have 1 clam, .

All of the above critters need Ca just like SPS, so this would be a bad reason to allow Ca to drop below ~350. Clams and LPS especially need Ca, just as much as SPS.

And while I don't test or need Mg, if you have to in order to keep levels right for your critters, then by all means you should do it. IMHO

[Johnny Reefer]

Originally Posted by reef_raf

All of the above critters need Ca just like SPS, ......

Yes, I know they do.

Originally Posted by reef_raf

.... so this would be a bad reason to allow Ca to drop below ~350. Clams and LPS especially need Ca, just as much as SPS.

Well, now I'm getting conflicting advice.
Hard to know what to go with.

Edit: I got clarification on the ~325 ppm Ca thing. Disregard. ~350 it is. Thanx Brad.

[Jaws]

I started dosing Mg after finding out mine was only at 1200 and natural sea water is well above that. I've never had that great coralline growth plus I've had poor coral growth as well as poor polyp extension. I haven't noticed a difference in coralline growth but my polyp extension has improved quite a bit probably also to do with the additional flow I added. I've also noticed a bit of an increase in growth and I'm still working on increasing it to the level it should be. I'm not sure how important Mg is for LPS and softies but because SPS are so finicky, I would definitely recommend dosing anything within reason that will mimic their natural habitat.

[reeferaddict]

Originally Posted by Johnny Reefer

Yes, I know they do.

Well, now I'm getting conflicting advice.
Hard to know what to go with.

Edit: I got clarification on the ~325 ppm Ca thing. Disregard. ~350 it is. Thanx Brad.

Hey Mark...

I don't understand what the conflicting advice is here....

ANYTHING that has a calcium carbonate skeleton or shell NEEDS Calcium and Magnesium... and more importantly... Carbonates... Alkalinity is consumed at a much higher rate than anything than anything else. Having said that, natural sea water values are what we have to shoot for for all these levels.... Mag is acceptable at 1250 - 1400 ppm... Cacium anywhere between 380 and 480... and Alk at 8 - 11 dKH... LPS may not demand as much as SPS... but they are still STONY corals... same with clams... Magnesium is used at a much slower rate than Calcium... but is important to keep the Calcium and Carbonate BIO available... I keep my Mag at around 1300 and only have to test monthly and dose every two weeks... all my make up water is run through my Kalkreactor... and using Kalk actually depletes the Magnesium... some people that use Calcium Reactors report not having to dose Mag at all, as is also the case with people with low calcification demands that do regular water changes. I've never read anything to the contrary of what I have just explained, but if anyone wants to butt in and correct me... please do.

[Johnny Reefer]

Originally Posted by reeferaddict

.... I don't understand what the conflicting advice is here....

Hey Jim. How’s it goin’?

Okay. Well…I’m not sure how to answer this without making a total fool of myself. I do not claim to have a chemically inclined mind and quite honestly find that part of the hobby the most difficult to grasp and consequently the least interesting. I prefer the biological aspect. (I dropped out of Chem 11 after two days). I suppose I may have jumped into this thread a little too hastily, as I have been stagnant and despondent with the hobby for a spell due to space logistics, and need to re-educate myself about some aspects of it. ( Read: I’m not sure that I know what the hell I’m talking about when it comes to chemistry).

The short answer is the conflicting advice is the 325 vs. 350 ppm Ca. The reason for the conflicting advice is…… simple maintenance vs. actual growth.

A bit of history…. (and I hope I’m not hijacking this thread as that is not my intent)….I was in the LFS the other day (one guess only as to which one) chinwaggin’ with an employee (one guess only as to who). I was in need of a new Mg test kit as the one I had was dead. I forget how the conversation went, but it basically led to me being told that the LFS’ tanks were basically at 325 ppm Ca and that Mg wasn’t really a concern in those tanks as it was generally a given that they are always at least 1150-1200 ppm. Now, one thing that easily escapes me, and is becoming increasingly more apparent when consulting this source for advice, is that this source is a retailer, not a hobbyist (per se). So the short and dirty is that the LFS I speak of is concerned simply with maintaining the organisms while the average hobbyist is looking for growth. Hence the conflicting advice. While an LFS’ advice may be well intended, it’s not necessarily accurate for the hobbyist. So that takes care of the Ca part. The Mg part.....well, I walked out of that store without buying a new Mg kit, not so much because the LFS doesn't test for Mg, but rather, I recalled that when I was first reading up on the hobby 2 years ago, none of the reference books that I purchased and read hardly mentioned Mg at all, let alone suggested testing for it. The only reason I did start testing for it was out of curiousity and that lead to dosing and hitting a target parameter due to "unsatisfactory" results.

Hope this answers your question......?,

[reeferaddict]

Heya Mark! I'm doing great! Thanks for asking!

Allright... Mr or Ms. LFS has a different agenda than us reef geeks... they gotta maintain an organism for a short time... We need to do it long term... AND make them thrive and prosper... If your Mag is at 1100 and your Ca+ is at 350... then that just means that your animals will wither away a little slower than if the levels are at 900 and 250...

And lookit... I ain't no expert here... but what I do know is that 1250 - 1400 ppm Mag, 380 - 440 ppm Calcium and 8 - 11 dKH Alk is what NSW values are around a natural reef and what the animals grow and calcify at optimal rates that are equally as tied to current, lighting etc etc etc etc... there are almost too many variables which is why there is no ONE way to do this right... but these chemical elements are well within our grasp to control, so we might as well do it right?

It's taken me a few years to get as much figured out as I have which probably doesn't amount to much more than a pile of coonsh*t, but what the hey... I just can't help sharing...

[Johnny Reefer]

Well, I couldn't help myself and tested Mg today. Ha ha. .
Um....can I change my vote? Yes, I bother. Yes, I test. Sometimes it's okay, other times I need to dose. Today it's okay.

Cheers,

[Farrmanchu]

It wasn't an option in the Vote, but I dose with Mg, and don't test. Adding the right amount to the WC water is all I do, with great results so far.