Kalkwasser: another thread

Discussion in 'Water Parameters and Additives' started by Oopkrane, 19 Mar 2014.

  1. Oopkrane

    Oopkrane

    Joined:
    23 Jul 2013
    Posts:
    112
    Likes Received:
    4
    Location:
    Brackenfell, Western Cape
    Have been doing some reading on kalkwasser and currently dosing. My frustration is that the kalk is not doing what its supposed to, keeping kH and Ca stable.

    I am mixing 1 tsp kalk per 2l RO water and dosing 10 ml per hour. So in total 240ml per day. Total tank water volume (excl substrate and LR) is around 137l. I only have softies, two hammer corals, fire tip and one small birds nest. I replace about 1 liter of evaporated water daily so I don’t think its due to a lack of evaporation.

    Current alk is 8.5 dKH and Ca is 400. I measure at around 7 PM each day. Alk drops by about 0.5 per day and Ca around 10 ppm. I then dose bicarb of soda and Seachem reef fusion Ca to get the values back up.

    Any ideas welcome?
    I am considering stopping the kalk dosing and mixing the bicarb with RO water for use in my doser. Question, will the bicarb solution work for dosing? Can I add vinegar to the mixture for carbon dosing?

    Thanks!
     
  2. AdS Guest




    to hide all adverts.
  3. Nemos Janitor

    Nemos Janitor

    Joined:
    7 Feb 2009
    Posts:
    8,384
    Likes Received:
    286
    Location:
    Joe's Mountain
    What is your salinity? and Magnesium?
     
    Last edited: 19 Mar 2014
  4. Nemos Janitor

    Nemos Janitor

    Joined:
    7 Feb 2009
    Posts:
    8,384
    Likes Received:
    286
    Location:
    Joe's Mountain
    If you're salinity is close to S=35 the following observations are.

    1) Your Ca and alkalinity are in balance and fall into the red zone. However the alkalinity is a
    little high for the Ca and very close to zone 3. That would indicate that you are dosing slightly more alkalinity or slightly less Ca. In other words you are dosing slightly out of balance. Not much though.

    2) For the invertebrate you have, the Ca and alkalinity loss is high. That would indicate that the Ca and Alkalinity is precipitating out of solution rather than being consumed by the invertebrates. The cause of the precipitation could be either very high pH or low magnesium.

    3) Ca and alkalinity could be consumed by calcareous algae or caulerpa if you have. But still, your consumption is more in line with precipitation.

    4) It would seem that the Kalkwasser is precipitating out of solution before it has the chance to dissolve. I would not worry to much on trying to find various ways to administer the kalkwasser until you have the precipitation issue sorted.

    5) An alkalinity of 8.5dKH is = meq/L 3.04

    The zones and balance I refer to are in this article.

    Chemistry And The Aquarium: Solving Calcium And Alkalinity Problems
     
    Last edited: 19 Mar 2014
  5. Oopkrane

    Oopkrane Thread Starter

    Joined:
    23 Jul 2013
    Posts:
    112
    Likes Received:
    4
    Location:
    Brackenfell, Western Cape
    Thanks. Sg is normally 1.026 and Mg 1500 mg/l, ph around 8.1. I will test all three to confirm tonight.
     
  6. Oopkrane

    Oopkrane Thread Starter

    Joined:
    23 Jul 2013
    Posts:
    112
    Likes Received:
    4
    Location:
    Brackenfell, Western Cape
    Hi.
    Test results:
    dkH = 10.2
    Ca = 400 ppm
    SG = 1.027
    pH = 8.2
    Mg = 2880 mg/l

    My main concern is the Mg. I have no idea why it is that high as I never dose Mg. ( I must add it has always been in the 1600 region, but never that high).
    I do weekly 8% water changes with Red Sea salt and RO water mix.

    I added 12ml vinegar to my Kalk mix (1L) and also now dosing in a much higher flow are of sump.

    Cheerio
     
  7. Oopkrane

    Oopkrane Thread Starter

    Joined:
    23 Jul 2013
    Posts:
    112
    Likes Received:
    4
    Location:
    Brackenfell, Western Cape
    ps. Ca, Alk and Mg tested with salifert kits.
    PH tested with digital meter
    Salinity with hydrometer
     
  8. Nemos Janitor

    Nemos Janitor

    Joined:
    7 Feb 2009
    Posts:
    8,384
    Likes Received:
    286
    Location:
    Joe's Mountain
    Yes something is not quite right regarding Mg.

    What test kits are you using?
     
  9. Nemos Janitor

    Nemos Janitor

    Joined:
    7 Feb 2009
    Posts:
    8,384
    Likes Received:
    286
    Location:
    Joe's Mountain
    Sorry I did not see you previous post.

    I would suggest that you get the test results confirmed by another test kit. Perhaps a reefing buddy with another make of test kit. Or a reliable LFS. We just need to confirm that the parameters are in fact what they are before embarking on remedies.
     
  10. Oopkrane

    Oopkrane Thread Starter

    Joined:
    23 Jul 2013
    Posts:
    112
    Likes Received:
    4
    Location:
    Brackenfell, Western Cape
    Thanks. I will do that over the weekend.
     
  11. Nemos Janitor

    Nemos Janitor

    Joined:
    7 Feb 2009
    Posts:
    8,384
    Likes Received:
    286
    Location:
    Joe's Mountain
    Funny how one wakes up in the middle of the night and the mind tells you to check something or gives an idea.

    You said you were dosing Seachem Reef Fusion Ca. I assume you are only dosing the Reef fusion 1 and not the Reef fusion 2 as well. If this is the case then this is where your Mg is coming from. Also remember that the red sea salt you are using is a high Mg salt.

    Quote from the Seachem web.

    "Reef Fusion 1™ provides not only 100,000 mg/L of ionic calcium, but also includes biologically appropriate levels of magnesium, strontium, boron, iron, manganese, and molybdenum."

    Seachem. Reef Fusion

    What is happening is that your dKH is very high for your Ca and is causing both to fall out of solution. By adding the fusion 1 you are adding Mg which is not being consumed. The Ca is precipitating out of solution due to the high KH. So in effect you are only dosing the Mg part of the Reef fusion.

    So the above makes sense as to why your Mg level is so high.

    Following is a suggestion if your Mg and other parameters you tested are correct. I would also suggest just rechecking the salinity as well, because it could be higher than you think. Recheck the calibration of the refractometer.

    So what to do to fix the high dKH and raise Ca whilst reducing your Mg down to 1300 to 1400ppm?

    This is going to be a complex process and will take some time to get parameters in check. The first things to do is stop dosing any form of alkalinity and let the alkalinity fall to about 7 dKH. Also stop dosing Reef fusion 1 until your parameters are in check as we don't want to add anything that has Mg in it where possible. You must slowly increase Ca to about 480ppm by using Seachem Reef calcium (Seachem. Reef Calcium) or any Ca product that does not have Mg. Even Calcium chloride will do. Also you will need to stop dosing Kalkwasser as it also has Mg in it. By doing this we are going to precipitate alkalinity (carbonate) We need to keep an eye on the alkalinity as we do not want it to drop below 7dKH

    To bring down the Mg is the difficult part. We can hope that by increasing the Ca that some of the Magnesium carbonate also precipitates. Water changes are probably the best way to reduce Mg but you are using Red Sea salt which is high in Mg. I would suggest that until your parameters are stabilized, using a brand that is not high in Mg, but that would mean that you would have to adjust the Ca and alkalinity of the change water before doing the water changes.
     
    Last edited: 20 Mar 2014
  12. Nemos Janitor

    Nemos Janitor

    Joined:
    7 Feb 2009
    Posts:
    8,384
    Likes Received:
    286
    Location:
    Joe's Mountain
    I assume that you would also have elevated levels in your tank, of some of the other elements in Reef fusion 1, like Strontium etc

    Please don't get the impression that the Seachem reef fusion product is on good. There are just situations in this case that make it unsuitable for the way you are using it.
     
    Last edited: 20 Mar 2014
  13. Oopkrane

    Oopkrane Thread Starter

    Joined:
    23 Jul 2013
    Posts:
    112
    Likes Received:
    4
    Location:
    Brackenfell, Western Cape
    Hi Keith. Excellent advise and thanks for your interest!
    To answer your questions from the top down: I am only dosing reef fusion 1 (Ca), not 2 (alk).
    I will check accuracy of refractometer.

    Ok, so I will stop all dosing, let alk drop to 7 and keep it there with Bicarbonate of soda. I will get Seachem reef calcium and dose accordingly to get Ca up to 480-500.
    Will keep you posted. Thanks.
     
  14. Oopkrane

    Oopkrane Thread Starter

    Joined:
    23 Jul 2013
    Posts:
    112
    Likes Received:
    4
    Location:
    Brackenfell, Western Cape
    Some feedback. I did a 20% water change and also dripped calcium over the weekend.
    Ca is now 500 and Alk still 9 dKh.
    Verified my Ca test results are accurate (LFS tested same result) and also hydrometer spot on.
    Unfortunately LFS could not test Mg when I was there. Will test current level tonight.
    Cheers
     
Recent Posts

Loading...
Similar Threads - Kalkwasser another thread Forum Date
[wtd] Reef Octopus Kalkwasser Stirrer KS-100 Wanted 20 Jan 2016
[wtd] Reef Octopus Kalkwasser Stirrer KS 150 Wanted 19 Jan 2016
Kalkwasser drip Water Parameters and Additives 6 Sep 2015
kalkwasser motor noise General Discussions and Advice 15 Apr 2015
Kalkwasser General Discussions and Advice 26 Dec 2014
kalkwasser question Water Parameters and Additives 11 Dec 2014
Dripping Kalkwasser and Bio Pellets Water Parameters and Additives 8 Aug 2014