Weird Science

[reefrunner69]

OK, I have been needing to test Mag for awhile, so today I picked up a test kit. The results were quite astonishing....2125 ppm . So what effect does high Mag have on your tank? I have not double checked the results or tested the reference (will do that in the AM). CA were in decent shape, 400 ppm CA and 3.77 meq/l ALK. Any thoughts? Water change is mixing and planned for the morning, with a different brand of salt, if the Mag is truely that high, it has to be from the salt, I have never added any magnesium to my tank and I use Instant Ocean salt (until today). Funny part is I expected it to be low, I have a mangrove in the fuge.

 

[ReefRaff]

how much was the kit, since I also use Instant Ocean and wish to test it.

 

[reefrunner69]

I got a SeaChem kit (cause it is what the LFS had) and it was about 40.00, but does 75 tests of Mag, Borate and Carbonate.

 

[ReefRaff]

was that Reef Status Magnesium Carbonate? cause if so you paid like 15.00 too much

http://www.thatpetplace.com/intro/main.html

serch fish/testing equip/seachem labertorys

25. and change

 

[steve-s]

OK, I have been needing to test Mag for awhile, so today I picked up a test kit. The results were quite astonishing....2125 ppm . So what effect does high Mag have on your tank?

For the most part none really with the exception of bivalves (and rarely univalves). If you have clams and such, they would be the first affected if there was anything to use as a "meter".

I would be curious of the results of a "feshly" made batch as well as a test of the tank water after the trade out.

I have never added any magnesium to my tank and I use Instant Ocean salt (until today). Funny part is I expected it to be low, I have a mangrove in the fuge.

That is strange!! 8O but possibley the one plant is not enough to pull the levels down. Any chance you have other additives that contain Mg or possibley Sr?

Cheers
Steve

 

[reefrunner69]

The Kent two part has Mg in it, but that is all, and the amount should be negligable. I have used it in the past and needed to add Mg. I have been using that for less than a week, the oly other thing I add is Kalk, nightly, but not enough t replace all evaporation, usually ends up being about 1/2 the daily evaporation.

Paying a little too much when you want it now, is one of the things we have to deal with. Oh well I don't mind supporting the LFS, they have given me excellent deals on other stuff, I wanted it today and they were there

 

[kcolagio]

And I quote a site on the web....namely: http://www.aquarium.net/0497/0497_3.shtml

Magnesium is roughly three times more abundant than calcium in natural sea water (1.295g/kg versus 0.412g/kg). Yet it plays a vital part in the whole carbonate scheme of things. This is what keeps the oceans supersaturated in respect to calcite.

---------snip-------------

So your magnesium is a bit high (about 2x what it should be), but from what I was reading, it won't make much difference to living things (at least, not in a detrimental way).

Here's something else I found... http://www.animalnetwork.com/fish/library/articleview2.asp?Section=&RecordNo=2856

Magnesium: Calcium's little sister

by Randy Holmes-Farley

Magnesium is an interesting atom that has tremendous biological and chemical relevance to reef tanks. Fortunately for reefkeepers, it is present in abundance in seawater and is depleted only slowly. Consequently, maintenance of magnesium levels is not typically a big issue if using an appropriate salt mix. Nevertheless, magnesium is a very important ion and engenders much discussion among hobbyists. In this article I'll try to add to the extensive writings that Craig Bingman has published in the past.

First, a little background on magnesium. In seawater, magnesium is invariably present in the form of a divalent cation, Mg++. It is present in seawater at a concentration of about 1300 ppm, and that concentration does not vary appreciably with depth or location in the world (besides estuaries and other places where all ions are distorted). In seawater, Mg ions outnumber Ca ions by a factor of 5. Most magnesium in seawater is present as the free ion hydrated with tightly bound water molecules. Some of it, however, forms tight ion pairs (i.e., soluble complexes) with negatively charged ions, such as sulfate, bicarbonate, carbonate, borate, fluoride and hydroxide.

--------------snip ---------------------

Personally, I'd just do a few water changes and then recheck it. Also, recheck your test kit against the baseline they give.

Kevin Colagio
Reef Geek.
http://www.PersonalReefs.com

 

[reefrunner69]

OK, so nothing is at risk...whew!!!

New tests:
Reference tested at 1350ppm, which is what was cited on the front of the bottle, so the kit works properly.

Tank water, 2125ppm
Tropic Marin salt (mixed for several hours) 1375ppm

The newly mixed water also clears my RO water, since it was mixed with the RO water. Water change is planned for tomorrow and will up the schedule to reduce the Mg levels in the tank

 

[gooyferret]

This may sound stupid but how do you check for Calcium? Is there test kits somewhere and where can you find them? With a reef aquarium what all should you check for with corals? Thanks!

 

[reefrunner69]

Yes CA test kits are available as well as alkalinity and Mg. Look to online vendors for the best prices.

I test regularly for:
CA
Alk
Mg (now)
PO4
SG
Nitrates

 

[kcolagio]

Here's a link to my retailers entry on this site... http://www.aquariumadvice.com/viewtopic.php?p=46271

I'll leave the advertising at that.

Kevin Colagio
Reef Geek.
http://www.PersonalReefs.com

 

[HoopsGuru]

So what does the test kit say for freshly mixed Instant Ocean water?

 

[reefrunner69]

You don't want to know, especially if your using it.

 

[reefrunner69]

Newly mixed IO @ 1.026

CA: 350
Alk: 6 meq/L
Mg: 2500 ppm

Can't speak for your bags of IO, but mine sucks!!

 

[kcolagio]

Just helps keep things in solution...you know, calcium, carbonates...stuff like that.

Of course, that stops things that need them (calcium and carbonates) from growing so fast.

I'll have to remember that about IO....*puzzle pieces snap together*

Later.

 

[Salt4Us]

Well I guess that would be why when we've ever tested our Calcium that it's been up there and haven't had to add anything. Is that why you decided to change from IO? What are the differences in readings on the newly mixed brand you are using now Kevin? Just curious.

 

[reefrunner69]

I switched to Tropic Marin, the readings were:
SG: 1.026
CA: 410 ppm
Alk: 3.77
Mg: 1125 ppm

 

[steve-s]

Newly mixed IO @ 1.026

CA: 350
Alk: 6 meq/L
Mg: 2500 ppm

Can't speak for your bags of IO, but mine sucks!!

My alk test ran out so I'll be testing mine this weekend. All I have to say is the nasty business with my monti caps had me freeked. I did a water change with IO salt a little over a week ago and they all dulled up and one started to flake.

Nail biting is almost done with though. I think once I confirm the tests I will be going back to Kent's.

Cheers
Steve

 

[reefrunner69]

I have heard good things about Kent's salt, but it is not available from my LFS, when you go back, I would be very interested to see te test results on it, maybe I can talk the LFS into carrying it.

 

[steve-s]

I have actually used Kent's salt since I started 7 years ago and have never had an issue. Last month my online had a sale on IO salts (including free pump ) so I said eh. why not.... I will definately get you the Kent results soon. I am too leary of using the IO with my nano's.

Oh well, live and learn. I'll just use it up on the FOWLR. 27g tank with 5 gal water changes twice monthly. Should only take me 2 years to lose the stuff...

Cheers
Steve