Welcome to Koi Forum. Is this your first visit? Register
Results 1 to 15 of 15
  1. #1
    Senior Member Rank = Rokusai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    357
    Thanks / Likes
    485

    Does granite raise ph?

    My ph has always been on the high side, 8+
    (Comes out the tap at 8.) Has been higher recently,
    been monitoring and slowing lowering it.
    There are some granite rocks in the filter pond that were there from the previous pond.
    I have read different answers to this,
    so does granite raise the ph?

    I know algae will raise ph through the day but does it not revert back overnight or does it stay elevated?

    I had got the ph down to 8 then went away over the weekend now back up to 8.6!
    So have got a trickle set up through the RO which I have anyway for work.
    Measured a 0.2 swing between 7.30am and 5pm I will check that again over the following days.

    Kh is pretty constant at 6 or 7, UV is on, water is clear but with algae on pond sides, does that need brushing/vacuuming of?
    From reading manky's web page, I see the bicarbonate that's normally used to raise ph will also set the upper limit at 8.4 is that the solution? (Ideally would like 7.5)
    What am I missing?



  2. Thanks Skoosh88 Thanked / Liked this Post
  3. #2
    Extreme Koi Member Rank = Kyusai Scamp's Avatar
    Join Date
    Nov 2014
    Posts
    1,087
    Thanks / Likes
    1192
    Hi Simon
    I have always considered granite as inert..I have used for years in aquaria, with no issue, so in my opinion should be fine. PH levels rise during the day as you mention..mine does, but not by much usually between 8 and 8.2 and drops down at night. So similar to yours, fish have no issue with that.
    I live in Bucks and waters hard from the tap (around 7.7) My KH is 9 and GH at 15. What test kit are you using, have you double checked your readings with another kit? Are you fish looking fit and healthy, or you have some concerns with their health? Cheers

  4. Thanks Simon Fish, freddyboy, RS2OOO Thanked / Liked this Post
  5. #3
    Senior Member Rank = Rokusai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    357
    Thanks / Likes
    485
    For ph I have api and a tetra kit,
    The reading was always high but when looking at a colour with only .5 variation it's an uncertain reading.
    So I recently got a ph pen thing, its quick to use and gives a precise figure eg, 8.19 that was at 8 am.

    I always thought the granite was fine, just that the reading keep going up despite efforts to reduce them.

  6. #4
    Senior Member Rank = Rokusai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    357
    Thanks / Likes
    485
    Fish seem ok there is the odd flash.
    Ph has been up to 8.8

    I will check on the rise later

  7. Thanks freddyboy Thanked / Liked this Post
  8. #5
    Senior Member Rank = Rokusai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    357
    Thanks / Likes
    485
    8 am, ph 8.19
    1pm 8.52
    7pm 8.71 that's despite having a good downpour of rain this afternoon.

    The other day when the swing was only .2 through the day it was after I had put a bit of ph down in, so must have limited the swing.
    Fish were not happy by tea time, reading a trace of ammonia so just algae for dinner.

    I can set the ro on a permanent trickle to reduce it, but there must be a better solution.
    The pond does get full sun most of the day, is shade the answer or more algae treatment or something else?

  9. #6
    Extreme Koi Member Rank = Kyusai Scamp's Avatar
    Join Date
    Nov 2014
    Posts
    1,087
    Thanks / Likes
    1192
    Hi Simon I agree the PH swing seems high to 8.7...how much algae is on the pond walls? Can you take a picture? Does the PH pen need calibrating out of the box, or good to go?
    I am not an expert at lowering PH levels, so I'll wait for someone who has experience of this and a workable solution to step in and offer you some advice..

  10. Thanks Simon Fish Thanked / Liked this Post
  11. #7
    Senior Member Rank = Rokusai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    357
    Thanks / Likes
    485
    The pen can be recalibrated but is ready to use.
    It only confirmed with more precise figures what the other tests showed.
    The algae is just like a slime on the surfaces.
    It had started to grow as string in the filter pond but after treatment is ok.
    Currently doing a 20% refill through the ro that will reduce it.
    I have a couple of koi encyclopedias that both refer to ph swings, one says 7-9 is ok the other says 7-11 is normal with no problems!! Fish were fine in the morning but not in the afternoon.
    I can't be the first to encounter this??
    Answers- water changes, shade, treat the algae, something else???

  12. #8
    Extreme Koi Member Rank = Adult Champion bowsaw's Avatar
    Join Date
    Aug 2015
    Location
    Bristol
    Posts
    1,663
    Thanks / Likes
    1105
    only if the granite is not pure might you see the pH alter
    the slow pond build thread

  13. Thanks Simon Fish Thanked / Liked this Post
  14. #9
    Senior Member Rank = Rokusai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    357
    Thanks / Likes
    485
    Not vital, so will remove it as a precaution.

  15. #10
    Extreme Koi Member Rank = Adult Champion bowsaw's Avatar
    Join Date
    Aug 2015
    Location
    Bristol
    Posts
    1,663
    Thanks / Likes
    1105
    remove to a bucket and do some before and after addition tests to see if it was the rock
    the slow pond build thread

  16. Thanks Simon Fish Thanked / Liked this Post
  17. #11
    Simon,

    Granite doesn't dissolve in water as long as the pH is above 7.0 but, as just said, if there are any impurities in it then they might dissolve. You could answer your question by taking a plastic bucket of dechlorinated tap water and monitoring its pH for a few days until it has stabilised, then you can add one of the rocks and continue monitoring the pH for a few more days or even weeks.

    I'm sure that you will find the granite innocent and you can then look for the real guilty party.

    You say that your pen meter is accurate but, for many years I've used pH probes that ranged from ludicrously expensive down to the types of probes that are commonly used in pen type meters and the one thing you can guarantee is that the readings cannot be guaranteed unless they have just been calibrated.

    I'm not saying your meter is inaccurate but this would be something I would always eliminate in situations where the drift in the probe could be responsible for inaccurate pH readings even with pH systems where very expensive probes were used.

    I had high accuracy standard pH solutions that I could always use to double check the accuracy of a probe if need be. You could verify the accuracy of your meter each time you use it if you have a standard pH solution you could measure first. A teaspoon of sodium bicarbonate in a cup of water would give you a pH of 8.4 which would be stable enough for koi pond purposes. You don't need to make a new solution each day if you kept it in a small sealed bottle that you could keep in a cool dark place, e.g. under the kitchen sink.

    BTW if your encyclopaedias say that variations in the pH of 7 to 9 or, worse still 7 to 11 are ok then you need to very carefully store them and I would suggest storing the in one of the storage boxes with wheels that your Council supplied. The blue one would be most suitable for this purpose.


  18. Thanks Scamp, Simon Fish Thanked / Liked this Post
  19. #12
    Senior Member Rank = Supreme Champion RS2OOO's Avatar
    Join Date
    Feb 2018
    Location
    South East
    Posts
    5,935
    Thanks / Likes
    13161
    Just for interest my PH is 9 today.

    Normally a solid 8.2 at all times, but currently have UV off for treatment and a fair amount of DOCs causing a brown bubbly sludge on the surface.

    My KH today was 14 dH, higher than what comes out the tap!

    What's really odd is that my tap water PH is 7.5 today, normally that is around 8.2 as well.

    So I topped up the pond a bit to dilute.

    Fortunately Ammonia is 0 mg/l, so no toxicity.
    Last edited by RS2OOO; 25-04-2019 at 07:39 PM.

  20. Thanks Simon Fish Thanked / Liked this Post
  21. #13
    Senior Member Rank = Rokusai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    357
    Thanks / Likes
    485
    There was a post recently about adding clay to the pond and it was mentioned that clay will raise pH.
    The biocenosis baskets I have in the anoxic pond are a clay litter. So have had the pump off to it for a week as a test.
    PH in the main pond has remained around 8.5 in the anoxic pond it went up to over 9, but without the pump on the algae in there has been able to get growing, so???

    So will the moller clay litter be raising the pH?
    Will it settle down after a while?
    Has anyone else had a pH rise wish adding clay biocenosis baskets?
    I have been keeping the pH stable by adding bicarbonate but it would be nice to have it lower.

  22. #14
    Moderator Rank = Supreme Champion Feline's Avatar
    Join Date
    Aug 2013
    Location
    Somerset
    Posts
    6,653
    Thanks / Likes
    5635
    Are you all stating your tap water pH for samples that have been left in an overnight container?
    There will generally be a pH rise of. up to 0.5 compared to what came out of the tap if you let it settle.
    Thats why pond water pH is almost always higher than fresh out of the tap pH, it's false and due to CO2 in the water not gassed off yet from underwater pipe runs.

  23. Thanks Simon Fish Thanked / Liked this Post
  24. #15
    Senior Member Rank = Rokusai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    357
    Thanks / Likes
    485
    Quote Originally Posted by Feline View Post
    Are you all stating your tap water pH for samples that have been left in an overnight container?
    There will generally be a pH rise of. up to 0.5 compared to what came out of the tap if you let it settle.
    Thats why pond water pH is almost always higher than fresh out of the tap pH, it's false and due to CO2 in the water not gassed off yet from underwater pipe runs.
    I will need to check that. But still wouldn't account for a steady rise to over 9.
    That's why I am looking for possible causes/ solutions.

 

 

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
All times are GMT +1. The time now is 10:25 AM. Online Koi Mag Forum
Powered by vBulletin® Version 4.2.3
Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.

vBulletin Improved By vBFoster® (Lite Version), © UltimateScheme, Ltd.