Cape Town pH, KH, GH

Discussion in 'Beginner Discussions' started by Dave Abes, May 16, 2015.

  1. Dave Abes

    Dave Abes

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    [FONT=Georgia, Times New Roman, Times, serif]Hi guys, hope you are all well.[/FONT]
    Could I bother the Cape Town folks for their latest pH, KH and GH readings, that would be very interesting to me.

    I'm based in the Southern Suburbs (very close to SAMS) and my reading, straight from the tap, after Prime are:
    pH: 9 or greater, but I expected this. Should drop over 24hrs
    KH: >1 and <2 dKH approx - estimated guess judged by the colour change on the second drop.
    GH - >3 and <4 dGH - this was challenging since the colour was very feint and the drops are green. No outstanding red -> brown -> green phases. More of a light brown to light green

    Thanks again oaks, if this topic has been covered, I couldn't find it, I did try.
    The next experiment will be adding crushed coral to a tank and recording the rise of the KH to 5-6dKH, which is what I will most likely be aiming for. And that will hopefully help me understand how much coral should be added to the filter for a time when I get the CO2 injection system in place.
     
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  3. Ebrahim

    Ebrahim

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    Howsit Dave Abes. Im in Mitchells Plain and ph of the tap water here is 7.6 when I last checked. I never checked kh and gh so I cant comment on that. The ph is quite high....do you think your test kit is accurate? When I use to use prime (very good product) I never got that high ph and buffer my water to get the ph to + 8.3 at least and I have crust Coral and limestone in my tank.
     
    Last edited: May 17, 2015
  4. Jwh

    Jwh

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    I would imagine that adding limestone or coral to your tank could make a very slight difference to hardness, but both coral and limestone dissolve very slowly, water changes will quickly flush away any gains in hardness? As Ebrahim suggests, you would have to buffer your water.

    I added some coral in a filter and saw no change in hardness at all.
     
  5. L2000

    L2000 aFISHionado

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    I'm in Penlyn Estate ,water out of tap also at 7,8 but I use peat ,driftwood ,coco moss ,Daro's PH down and on occassion distilled vinegar to get my water down to PH 6,5.No fish mortality , I have Angels ,Golden and German Blue Rams .Ancistrus ,Emperors ,Red Phantoms ,Glo Lights and some big ass neons as well as Otocinclus. It takes me approximately 2 -3 days to get my parameters back in check after a 40% water change.Oh yes I'm also running DIY CO2 for about 6months now
     
  6. morris

    morris

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    Are you sure about your ph?
    that higher than our water in joburg, which is very unlikely
     
  7. OP
    Dave Abes

    Dave Abes

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    Hey gents, thanks for the response, I'll be taking the water down for a test at the LFS and report back.
    But as far as I'm aware, the pH should drop because of the low KH, at least when placed in a tank,
    since it can fluctuate very easily due to the low KH buffering capacity.
     
  8. JCL

    JCL

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    @DaveAbes I am sure that your ph reading was right.
    In my experience a high ph (over 8, sometimes 9) is not uncommon.
    As you correctly state it will go down when letting the water stand 24 hrs or longer.
     
    Last edited by a moderator: Oct 2, 2016
  9. Marius

    Marius

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    I stay in Edgemead. Two years ago our PH was 7 from the tap. Now it is 8.0 after I let is stand. My Gh and KH is about the same as yours. The only time I would worry about the PH is if you are keeping Rams or Discus.
     
    Last edited: Jun 8, 2015
  10. Cale24

    Cale24

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    Anyone know the latest readings for Cape Town? I'm in Sea Point but will test soon.

    My tank's PH is around 6 - big piece of driftwood, and its been running 3 years. I am trying to transition to 50% tap water (currently all RO, which costs a bit all added up). The RO is about 6.8, and I just add it with a standard dose of Prime and Stability, nothing more, to be safe.
    I'm obsessed with rams so am really trying to lock down things. Lost a few over the past couple years, but not recently.

    Be nice for LFS to have monthly readings done and that info on a board for people to see.

    Edit: I used to use water from the Newlands Spring before it became abused by idiots. The PH was 5.6 (other levels also good) and my rams thrived.
     
    Last edited: Feb 1, 2019
  11. 2time

    2time Keanan

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    Good to know. I'm busy redoing my 450l setup and plan on filling it with spring water. Hopefully there wont be long lines when I get there.
     
  12. Cale24

    Cale24

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    @2time Yeah it became manic but I actually went there yesterday and it wasn't bad - 25l limit per usage, but you can go back and forth from car one barrel at a time, etc.
     
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  13. Hendre

    Hendre Polypterus freak

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    TDS here is extremely low, be careful with it guys. Sea shells are rich in calcium and will help keep your pH higher, just throw them on the filter and replace them when it's worn away.
     
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  14. Cale24

    Cale24

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    Just out of interest, some readings from the past week in Cape Town concerning this:

    2 day Aged tap:

    PH +- 7.6
    GH: 3 (53.4 ppm)
    KH: +- 1-2 (18 - 36 ppm)
    Ammonia: +-0.3 mg/l
    TDS: 67 ppm
    No2: 0 mg/l
    No3: 0 mg/l

    Also - TDS for water straight out the tap - Cold water 70ppm ; warm water 90ppm. Not entirely sure what to do with that info given the temperature and no idea what it constitutes, but thats what it is.

    Newlands Spring:

    PH: +-5.5
    GH: 1 (18 ppm)
    KH: 1 (18 ppm)
    Ammonia: 0.15 mg/l
    TDS: 58 ppm
    No2: 0 mg/l
    No3: 0 mg/l

    My established community tank gets Seachem Equilibrium with water changes, and I have some coral in there for the KH (plus plants and wood) but even so, the KH remains around 1-2. Softwater fish in it though so not had any problems for quite some time.

    I use 50% tap; 50% Spring water mix; with a 50% water change every week (ram cichlids asked for this).
     
  15. Cale24

    Cale24

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    Cape Town water (well, Sea Point at least) out of nowhere has a PH of 9.0, way up from the usual +-7.6 reading. Word of warning to anyone living here. I now have 2 rams suffering shock as a result of this bulls***.

    Tap TDS now reading +-40 ppm, down from 70. That also doesn't make sense to me given the super high PH.
     
    Last edited: May 27, 2019
  16. Hendre

    Hendre Polypterus freak

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    It's gases in the water to keep the pipes from corroding, you may notice lots of bubbles. pH will drop as the gas leaves the system
     
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  17. Cale24

    Cale24

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    Ah, so this is only a temporary issue? I did notice bubbles that seemed to resemble soap of all things, wasn't sure what to make of them.
    I eventually got through to the water department and they had no such explanation. All they said was "we can have the tap water as high as PH 9.7" and that the PH will vary depending on the source. 9.7 Seems excessive to me, given 8.4 is usually the highest for drinking water as far as I know.

    How often does this happen locally? Are there any warning signs or do I need to test tap PH more frequently in general?
     
  18. Hendre

    Hendre Polypterus freak

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    The high pH of tap shouldn't have too much of an impact, it swings back quickly. Just be careful for embolisms if you use lots of cold, gas saturated water.
     
  19. Cale24

    Cale24

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    Ok, just bad luck with timing I guess - tested it again and its back to around mid 7 range, from 9 this morning. So, seems to have shot up and stayed that way for 2 or 3 days from what I can tell, before coming down again.
    I know test strips are not that accurate but perhaps I'll get some as a quick general check ahead of WC in future.

    Thanks for the input.
     
  20. Chandz

    Chandz

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    Does anyone have any recent tap water KH and GH readings? I measured the PH yesterday and it was 8.9 straight out the tap.

    Sent from my SM-G965F using Tapatalk
     
  21. A new day

    A new day

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    Hi @Chandz I just did a Sera liquid pH test which came out as 8,5 which is strange for my area (Rondebosch). It used to be 7 from the tap but dropping within 2 weeks because my water is soft.

    I also just took 2 JBL Proscan tests but not sure that it’s accurate as it shows pH as <6 when Sera says it’s 8,5!!!

    Also the first one says nitrates are 18 but 2nd one 0, makes no sense.

    The KH of my water usually tests in the red zone but now higher than usual. Plus it didn’t pick up on any chlorine in the tap water. Not sure that I’ll attach much value to those readings.

    4BA4F168-2580-4E1E-8A43-F6AEE850BB70.png

    2214C3AC-9A9E-45A2-ACF8-C152949F5D82.png
     
    Last edited: Mar 8, 2020

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