Why Does My Alkalinity Go Up At Night?

Discussion in 'Water Chemistry' started by Servillius, Feb 29, 2012.

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  1. Servillius

    Servillius Montipora Digitata

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    I have it set so it only doses during the day, but my morning reading (before dosing starts) is consistently 10ppm higher than my evening reading (right after dosing stops).

    Any theories? Is this normal?
     
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  3. Corailline

    Corailline Super Moderator Staff Member

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    It is a dry heat, yeah right !
    Try correlating the to the difference in temp in the evening and in the am before the lights go on and see if you have a swing there, which will affect your SG value.
     
  4. NanaReefer

    NanaReefer Fu Manchu Lion Fish

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    What???
     
  5. Servillius

    Servillius Montipora Digitata

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    Total temp swing over the course of a day is about 1.5 degrees Fahrenheit. Temp peaks in e afternoon and is at its lowest in the morning. Is low temp causative of higher alkalinity?
     
  6. Corailline

    Corailline Super Moderator Staff Member

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    It is a dry heat, yeah right !
    I see diplomacy runs rampant in your neighborhood. :p


    Actually my mistake Servillius I read the post before I had my am coffee, and dyslexia is a huge issue I saw Salinity, my mistake.
     
  7. Servillius

    Servillius Montipora Digitata

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    No problem at all Coralline, the two hours of chemistry research trying to figure out how temp would affect the carbonate concentration was most informative :)

    I am at a loss now however. I just took two tests with my Hanna, and they read 162 and 177. I no longer trust the readings. They have been suspect for weeks and nothing seems to get me back to consistent.
     
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  9. Corailline

    Corailline Super Moderator Staff Member

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    It is a dry heat, yeah right !
    LOL, sorry.

    My morning alk is always lower than my night but not by that much. I manually does in the am right before the lights come on because of that.

    Bump for chemistry....ummm Steve, John, m2434, Curt.........
     
  10. Sacul1573

    Sacul1573 Millepora

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    I'd be curious to know what your PH swings are from am to pm.

    Isnt PH affected by alk dosing? (hence I dose alk at night)

    Thus, wouldnt a drop in PH overnight result in a drop in alk? or am I grasping at straws?

    EDIT: Whoops, I see the OP has the opposite problem. In which case my entire post is mute.::)
     
  11. mrstihl

    mrstihl Spanish Shawl Nudibranch

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    The PH of your water will affect the maximum amount of Carbonate and bicarb which also effects the ratio. Calcium that can remain in solution is also affected. If you are approaching the upper limits of what the water will hold in solution there is your answer. If it is something other than that, you've got me.