Rising Alk

Discussion in 'Reef Chemistry by Randy Holmes-Farley' started by mdbronco, Jun 8, 2019.

  1. mdbronco

    mdbronco Active Member

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    Hi,

    Over the past month, my alk keeps climbing steadily. I test the same time each week, and everything remains in line except the alk lately. Same salt since starting the tank over a year ago (RS Coral Pro). I change water the same time each week (10%). All rock has been in the tank for at least 6 months (last random pieces added then). Same test kit as always.

    Calcium 410
    Mag 1320
    Phos 0.25
    Nitrate - 0
    Nitrite - 0
    Ammonia - 0
    PH 8.2
    Alk - used to be 8 four weeks ago, now is 16
    Sal -1.026

    I have always dosed kalk in my ATO but I guess I should stop? Why is this creeping up? How do I remedy safely without disrupting everything else?

    Mixed reef, with SPS, LPS, and softies. Macro algae as well. What ill effects can be expected with this high of number?

    Thanks!
     

  2. Hemmdog

    Hemmdog Valuable Member R2R Supporter Build Thread Contributor Hospitality Award

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    Your coral has stopped consuming, most likely your phos being sky high with zero nitrates. Stop dosing kalk and get your phos down and feed your fish more good frozen food to get nitrate up.
     
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  3. Randy Holmes-Farley

    Randy Holmes-Farley Reef Chemist Staff Member Team R2R R2R Supporter R2R Excellence Award Article Contributor Expert Contributor

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    Because you are dosing too much. Use less.
     
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  4. mdbronco

    mdbronco Active Member

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    To the point :)

    thanks both!
     
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  5. Randy Holmes-Farley

    Randy Holmes-Farley Reef Chemist Staff Member Team R2R R2R Supporter R2R Excellence Award Article Contributor Expert Contributor

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    You're welcome.

    Good luck! :)
     
  6. Brett S

    Brett S Active Member

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    I wonder if there is a testing error. Either a bad test kit or a mistake made during testing. If your alkalinity really rose from 8 to 16dkh over 4 weeks then most of your corals would be dead. That is a huge jump over a reasonably short time period and 16 is well outside the safe range.

    The first thing I would do is get another test kit to verify that your alkalinity is really at 16dkh. If so then you need to bring it down, but you still want to bring it down reasonably slowly or you’ll just further shock anything that is still living. I might try to do a few water changes over a period of a few days to get it back down to a more reasonable number like 11 or 12dkh, but don’t drop it by more than 1dkh per day. Once it’s there then I would slow down even more and take a few weeks to get it back down to 8 or 9.

    But before you do anything too drastic get another test kit to verify that you really are at 16dkh
     
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  7. mdbronco

    mdbronco Active Member

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    Thanks for this. I ended up buying a different brand of test kit and it was verified. But I stopped dosing kalk in my ATO and just tested it again after 2 days. It has come down from 16 to 13. Things seem to be fine, in fact my softies seem happier than they have lately.

    My ignorance with kalk was that although of course you can always dose too much, I figured that once the saturation point was reached, it didn't really "matter" too much about putting an extra teaspoon or two into the mixture. Apparently this was wrong...
     
  8. Reefs and Geeks

    Reefs and Geeks Member

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    If using kalk in your ATO, it's possible you may have more evaporation than usual and therefore dosing more than usual without you knowing. I agree to stop dosing for now, monitor, and continue dosing at a reduced rate once levels come back down.
     
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  9. mdbronco

    mdbronco Active Member

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    Yes this makes a lot of sense actually.
     
  10. TitanCi

    TitanCi Valuable Member

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    That and also your salt is higher in alk too. Are you matching the alk of the salt to your display tank alk?
     
  11. mdbronco

    mdbronco Active Member

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    Sorry I don’t quite understand. I match the salinity obviously when doing water changes, but how would I go about matching the alk? RS Coral Pro has an alk of 11.5. Are you saying then that I shouldn’t use it if I’m shooting for a stable alk of 9-10?
     
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  12. TitanCi

    TitanCi Valuable Member

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    There are ways to bring down the alk of the mixed water before you add it to your display. If your display is 8.0 and you always add higher alk water change water each week, then it will increase your alk.

    You can use Seachem acid buffer or muriatic acid to reduce your alk in the water change water before you add it to your tank.
     
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  13. mdbronco

    mdbronco Active Member

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    Ok thanks. TBH this might start to get a bit over my comfort level, even though it sounds pretty straight forward. I used to own a pool company and am very familiar with muriatic acid and dosing etc, but hopefully I can get it back to the range it once was before going that route. Thanks for the tips!
     
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