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Home » Saltwater Aquarium Supplies  » Test Kits  » Specialty  »  Elos Aqua Test Kit - Magnesium
Elos Aqua Test Kit - Magnesium

Elos Aqua Test Kit - Magnesium

Average Rating 4 25
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Elos Aqua Test Kit - Magnesium Information

Product Manuals & Documentation


Magnesium (Mg) is present in a high quantity (1300-1350 ppm) in natural seawater. Contrary to its not only quantitative significance, this element was ignored as an important parameter of the marine aquarium for a long time.
We know today that Magnesium creates a remarkable improvement in the growth of calcareous algae and also has a positive influence on the growth of invertebrates and macro algae. The ideal value of Magnesium in the aquarium is: 1100-1300 mg/Lt for the marine aquarium. Because of the importance of Magnesium, it is necessary to keep the proper level by testing it with an accurate test kit.

ELOS AquaTest Mg, as well as all titrimetric test kits of this line, grant very high precision thanks to several procedures like the use of calibrated droppers with constant and predefined drops of 0.03 ml each, the validation of our reagents, through NIST (National Institute of Standard and Technology) validation and the careful stock management to supply to our customers ONLY the freshest production batch.


  • High quality system: one powder reagent and two liquids!
  • Standard sensibility: 100 ppm of Magnesium ions.
  • NIST validation: each batch of reagents is validated using NIST (National Institute of Standard and Technology) samples
  • "C" reagent available as separate sales unit
  • High number of test per kit: up to 50 test (with a standard Mg level of 1100 ppm)
  • "Safe reagents": reagents and testing procedures are based on Low Risk Reagents. None of our test kits are based on Toxic Reagents.

  • Manufacturer Info

    ELOS: the ultimate supplements and equipments for marine and planted aquariums.

    Elos is an aquaristik company that is exclusively dedicated towards the development, production, and marketing of specialised, high quality products for the aquarium market.

    We apply the latest advances in marine and fresh water sciences into our manufacturing and products. We are environmentally responsible as well as respectful of the key ethic rules on employment and production. Almost all our products are made in Italy, through few, well trained Internal Employee with the help of key external suppliers, Universities and Research Centres.

    Our commitment is to invest in the future, we take great care of details and innovations but beside this we also take care of our traditions. We apply modern process, but we also use traditional techniques, employing local craftsmen for the production.

    We take great care in designing our products, and packs to simplify their use making them pleasant to see and to touch. From the first contact with our products you will immediately perceive the care to produce them and the great attention toward each single detail.

    For all this we invite you, by heart, to try our products. Join your passion with us, use our products and make the best out of them and, we are sure, You will experience the delight of creating your personal, unique underwater world in a beauty you have never seen before.

    Elos Aqua Test Kit - Magnesium Reviews

    Average Rating
    (25 reviews)
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    of 3

    Easy to use and very accurate

    Reviewers Rating Excellent!

    Posted: 7/8/2015 from NORTHRIDGE, CA UNITED STATES
    5.0 5
    Experience Level: Intermediate

    Comments: What more can you ask for? It is very easy to use. Make sure you throw out the liquid after phase 1. Just keep track of the drops you put in. Then do phase 2 and keep track. Use their simple formula and you have a very accurate reading of your Mg. I used Salifert Mg test. I have found this one MUCH MUCH more accurate. Reagents are better, colors are easier to see; all in all it's just awesome

    Did you find this review helpful? Yes No

    Elos MG test kit

    Reviewers Rating Great

    Posted: 3/10/2014 from ELIZABETH, CO UNITED STATES
    3.5 5
    Experience Level: Intermediate

    Comments: Initially directions were a little confusing. Once I reread them the test was easy to do.

    Did you find this review helpful? Yes No

    Easy to use

    Reviewers Rating Excellent!

    Posted: 1/18/2012 from MORENO VALLEY, CA UNITED STATE
    5.0 5
    Experience Level: Intermediate

    Comments: My wife does the testing (I take care of almost everything else) so I can only relate to what she has told me. We tried a few other test kits and the ELOS seemed to be inline with test results from other kits. My wife likes the ELOS test kits because in her opinion they are easier to use and we seem to get fairly accurate results (compared with other test kits). We have never sent in samples to a lab but my tank is thriving so I'll go by that until I have the feeling to think otherwise.

    Did you find this review helpful? Yes No

    Avoid the Mg kit from Elos

    Reviewers Rating Unsatisfactory

    Posted: 11/23/2011 from GLENDORA, CA UNITED STATES
    0.5 5
    Experience Level: Expert

    Comments: I have always trusted Elos test kits and get good results with the CA and ALK kits. NOT THE SAME with the Mg kit. 1st test: reading 1600. Seemed high since I had not dosed for 2 months. Test 3 more times, same result. 2nd test: mixed new SW using Instant Ocean, 1700 was the result. Anyone familiar with this salt knows 1700 is impossible. 3rd test: took my tank water sample to LFS and they found my water to have a reading of 1150. Had them test the new mixed water, 1300. 4th test: had the LFS use my Elos kit and followed same directions, same outrageously high result. Contacted Elos and got the run around. After all the testing the regents are almost empty. Went back to Salifert, very reliable for Mg testing. I still use Elos for CA and ALK but with caution.

    1 of 1 People found this review helpful, did you? Yes No

    Magnesium testing

    Reviewers Rating Average

    Posted: 3/19/2011 from LOS ANGELES, CA UNITED STATES
    3.0 5
    Experience Level: Intermediate

    Comments: Good product, bad instructions. They do not tell you at least in the english verision that you have to dump the solution from pahse one of test bottle, and refill with aquarium water for phase two. I would have used all of part D, if I had not taken the time to research the intreuctions on line.

    2 of 2 People found this review helpful, did you? Yes No

    Elos Vs Salifert

    Reviewers Rating Great

    Posted: 12/16/2010 from Chicago, IL UNITED STATES
    4.0 5
    Experience Level: Expert

    Comments: Salifert is easier and quicker. Tried this one out only because rep told me it sells more. It gives you readings in a scale of 50 (i.e. 1300, 1350, 1400, 1450......). Still a good test but prefer Salifert due to "tighter" readings and quicker results.

    1 of 1 People found this review helpful, did you? Yes No

    Easy to use

    Reviewers Rating Great

    Posted: 5/28/2010 from RENO, NV UNITED STATES
    4.0 5
    Experience Level: Intermediate

    Comments: This test kit is very easy to use, if you have already used alkalinity/calcium test kits you should have no trouble using this one. You will need to take 2 samples from your fish tank and count the number of drops it takes for the water to change its color using different chemicals with each sample. Then make a quick math to calculate the concentration of magnesium. The precision if of 50 ppm, which is good. The only down side is the test tube that comes with the product. Mine broke on the first time I tried to use it. This is not an issue since I have several test tubes from other kits. That is the only reason I don't give it a 5-star rating.

    Did you find this review helpful? Yes No


    Reviewers Rating Unsatisfactory

    Posted: 3/19/2010 from DORAL, FL UNITED STATES
    1.0 5
    Experience Level: Expert

    Comments: The test vial is very fragile and likely to break upon inserting or removing the stopper driving shards of glass into your hand. DO NOT BUY!!!

    1 of 3 People found this review helpful, did you? Yes No


    Reviewers Rating Excellent!

    Posted: 3/3/2010 from KALISPELL, MT UNITED STATES
    5.0 5
    Experience Level: Intermediate

    Comments: Once you get the hang of how to use this test kit, it's actually very easy. I read a couple of the reviewers comments before ordering it, and learned that the key here is that this is a TWO PART TEST. Be sure to dump out the first color change from red/orange to green; then count drops again for the color change from pink to blue. Color change is very dramatic and easy to see, and the test is accurate to increments of 50.

    1 of 1 People found this review helpful, did you? Yes No

    Good Test Kit

    Reviewers Rating Excellent!

    Posted: 2/16/2010 from DALLAS, TX UNITED STATES
    5.0 5
    Experience Level: Expert

    Comments: A agree with the person that put one star about the directions. I did the test 3 times before I figured out I wasn't dumping out the first phase test. So I wasted a lot of drops. To save anyone some frustration after the water turns green from test bottle A... dump out the water before going to the next test phase. So the directions could be more clear but I ended up liking the test vs. other popular brand. One reason is it can measure well above 1500. And I have added too much Mg more than once. The last brand I was using maxes out around 1500 cuz the syringe simply won't hold more. As far as 100 increments that's what I was expecting from reading about it but my directions lead me in 50 increments. On the second phase .. .if you have drops after the math.. it would be 1200... 26 drops would be 1250.

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    of 3
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