Alkalinity : What dKH do you target and why?

Discussion in 'Water Chemistry' started by NASAGeek, Jan 30, 2010.

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

What dKH do you target?

  1. <=7

    3.0%
  2. 8

    9.1%
  3. 9

    21.2%
  4. 10

    30.3%
  5. 11

    9.1%
  6. 12

    21.2%
  7. >12

    12.1%
Multiple votes are allowed.
  1. 2in10

    2in10 Super Moderator Staff Member

    Joined:
    Aug 6, 2009
    Messages:
    19,258
    Location:
    Sparks, NV
    I target 4 to 5 meq alkalinity, 11.2 to 14 dKH
    I use Seachem Reef Builder and Seachem alkalinity test kit.
     
  2. Click Here!

  3. Peredhil

    Peredhil Giant Squid

    Joined:
    Aug 20, 2008
    Messages:
    5,176
    Location:
    Texas
    What dKH do you target? 13
    How do you measure dKH?? (which kit or other means?) API
    What method do you use to maintain dKH? BRS Two-Part auto dosing

    Why: When I keep my Mg at 1500 and Ca at 450, it just kind of wound up there with a steady pH of 8.4. Corals happy. I'm happy.

    Autodosing has been extremely stable.
     
  4. NASAGeek

    NASAGeek Eyelash Blennie

    Joined:
    Nov 16, 2009
    Messages:
    1,253
    Location:
    Houston, TX
    Interesting that in a hobby that is so precise in so many areas that there is so much variability in Alkalinity. Why is that? Since Alk is one of the main parameters, why so much variation? Also, since natural reefs are 8, I think, why is it recommended to keep reef aquariums so much higher?

    Hmmmm.... interesting.

    M
     
  5. Robman

    Robman Great White Shark

    Joined:
    Jan 22, 2009
    Messages:
    2,688
    Location:
    Katy, Tx.
    I shoot for 10dkh cause it is in the middle!!
     
  6. bje

    bje Long-fin Bannerfish

    Joined:
    Apr 12, 2009
    Messages:
    1,628
    Location:
    Illinois
    I just started my tank 2 months ago, but here are my answers:

    What dKH do you target? 10
    How do you measure dKH?? (which kit or other means?) API Test Kit
    What method do you use to maintain dKH? Bottle of seachem calc/alk that I am hand dosing for now until I REALLY need a 2part system and when I do get to that point where I have enough corals to suck up the calc/alk ill go with a BRS two part
     
  7. bje

    bje Long-fin Bannerfish

    Joined:
    Apr 12, 2009
    Messages:
    1,628
    Location:
    Illinois
    Well IMO if you keep it at 10 you shouldnt go below 8 which could harm corals. Keeping it at 10 gives you a slight buffer zone so if you tested in the morning and saw that you were at 10 after dosing but at night you drop to 8 and you dose again back to 10 for the following day you're good.

    Im sure the ocean isnt at a constant 8 either. Im sure it has some form of rise/fall effect.

    As I understand it having a CA Reactor on your system will help maintain this level more adequately because you're not having to 'dose' the system. There in lies one of the pro's/con's of 2-part versus a reactor setup.
     
  8. Click Here!

  9. horkn

    horkn Giant Squid

    Joined:
    Apr 4, 2009
    Messages:
    3,200
    Location:
    Cedarburg, Wi
    I keep my alk at 10.4 dkh

    I use salifert's alk test kit

    To maintain my alk I use a geo calcium reactor

    Yes, having a calcium reactor auto doses the calcium, alk and mag, while a 2 part you need to constantly test to make sure you are doing the right amount.

    The only negatives to a reactor versus 2 part is, cost, and some reactors can lower the ph of the tank. GEO's don't have that ph issue.
     
  10. NASAGeek

    NASAGeek Eyelash Blennie

    Joined:
    Nov 16, 2009
    Messages:
    1,253
    Location:
    Houston, TX
    Trying to learn more here...

    So how much does Alk normally varying during a 24 hour period and why does it vary? Lighting cycle??

    Off to go research and read some more....

    M
     
  11. GuitarMan89

    GuitarMan89 Giant Squid

    Joined:
    Mar 31, 2008
    Messages:
    5,736
    Location:
    Wilmington, DE
    I now target at 8. Natural sea water is around 7 and for some reason I just can' t raise it much higher for long periods of time, so I just started maintaining it around 8.
     
  12. grubbsj

    grubbsj Gigas Clam

    Joined:
    Sep 28, 2006
    Messages:
    856
    Location:
    Outside of Seattle, WA
    ...closing in on a control band of 12 -14 dkh (this morning, 10.6)
    ... Salfast test kit
    ...will be Ca Reactor (BRS 2 part)

    The this DT started 10 weeks ago...

    First step is to get the pH/Alk stabalized while bring up Ca & Mg. I'm using some chems left over from my earlier tanks...All new purchases are BRS 2 part.

    I suspect that I have 2 - 3 weeks before all comes in line and I can start the Ca Reactor.