Low Magnesium

Discussion in 'Water Chemistry' started by reefnJeff, Dec 5, 2012.

to remove this notice and enjoy 3reef content with less ads. 3reef membership is free.

  1. reefnJeff

    reefnJeff Pajama Cardinal

    Joined:
    Feb 14, 2012
    Messages:
    1,412
    Location:
    Saint Cloud, MN
    I got me a MG test kit finally, a Red Sea Mg pro. The test showed my Mg level below 760 ppm. I understand there can be a few ill side effects from low Mg, it just so happens i been having low PH issues also, is this related? and how do I safely get the Mg to normal levels?
     
  2. Click Here!

  3. 2in10

    2in10 Super Moderator Staff Member

    Joined:
    Aug 6, 2009
    Messages:
    19,258
    Location:
    Sparks, NV
    There probably little to no pH relationship. You will need to aerate your house to lower CO2 levels to get your pH down along with increase surface agitation to increase gas exchange.

    You will need to purchase a magnesium supplement to increase your levels. Do not increase more than 100ppm per day. Keep your levels between 1280ppm and 1350ppm.

    You can purchase Mg from BRS which would be your most cost effective way or buy any commercial brand.
     
  4. reefnJeff

    reefnJeff Pajama Cardinal

    Joined:
    Feb 14, 2012
    Messages:
    1,412
    Location:
    Saint Cloud, MN
    My PH has been running at an avg of 7.6 CO2 huh!! Will I can't open windows its winter ;) i'll think of something. maybe a CO2 filter.
     
  5. kwmjones

    kwmjones Flamingo Tongue

    Joined:
    Sep 26, 2010
    Messages:
    117
  6. kwmjones

    kwmjones Flamingo Tongue

    Joined:
    Sep 26, 2010
    Messages:
    117
    Reading through that article, there actually is a relationship between pH and Calcium and Alkalinity - a lower pH allows more calcium and alkalinity to be kept in solution without precipitation, and a higher pH makes for quicker calcifying of these two, where magnesium keeps the calcium and alkalinity ions from coming together prematurely so the corals can use them as intended. At least, thats how I read it:)
     
    ncfishguy likes this.
  7. kwmjones

    kwmjones Flamingo Tongue

    Joined:
    Sep 26, 2010
    Messages:
    117
    I'll leave you alone after this, but here is a link to all of Randy Holmes Farley's articles - seriously important stuff for keeping reefs and understanding the chemistry behind it. Very easy to understand and provides a wealth of information about all levels of chemistry within your system.

    Reef Chemistry Articles - Reef Central Online Community Archives
     
  8. Click Here!

  9. Marshall O

    Marshall O Giant Squid

    Joined:
    Jun 19, 2012
    Messages:
    3,517
    Location:
    Central MA
    Just to make sure you are testing correctly, and before you add any mag to your tank, test a brand new batch of SW and see what you get. If it matches what the manufacturer says it should be, retest your tank again. If you still get the same number, then start to dose.

    The first time I tested I think I started off with the wrong amount of tank water by mistake, which of course skewed the results.
     
  10. kwmjones

    kwmjones Flamingo Tongue

    Joined:
    Sep 26, 2010
    Messages:
    117
  11. Corailline

    Corailline Super Moderator Staff Member

    Joined:
    Sep 8, 2010
    Messages:
    19,652
    Location:
    It is a dry heat, yeah right !
    Raise the Magnesium 100/ppm each 24 hours until you get to 1250-1300.

    Alkalinity the buffer is the tanks ability to maintain a stable pH. If the Magnesium is low it affects alkalinity there by lowering the pH.

    Alk is a better value for measurement with SW tanks than pH IMO. I have not measured pH in years but use the Alk values instead.
     
  12. Vinnyboombatz

    Vinnyboombatz Giant Squid

    Joined:
    Oct 24, 2010
    Messages:
    6,344
    Location:
    Dunnellon, Florida
    Absolutely solid advise.;)
    Your Magnesium should be roughly 3 times your desired Calcium level.Most of us strive for a Calcium number between 400-450 so your target for Magnesium should be in the 1200-1350 range. Low Magnesium levels can cause your Alk. and Calcium to fall out of solution and swing wildly affecting the PH level.