AquaticSuppliers.com     Golden State Discus

Results 1 to 11 of 11

Thread: CO2, pH, and water changes

  1. #1
    Registered Member
    Join Date
    Aug 2018
    Posts
    29

    Default CO2, pH, and water changes

    So I’ve always been told stability is the key with discus. My question is if I age the water to the same temp and do a water change into a tank that has CO2 will the pH change be harmful? The CO2 water will be lower than that of the aging barrel. I’m not doing this on my discus tank but on a planted community tank. Some day I might want to add discus though. Thanks for the help

  2. #2
    Registered Member
    Join Date
    Apr 2016
    Location
    Warren Mi,
    Posts
    76
    Real Name
    Ed

    Default Re: CO2, pH, and water changes

    Normally the ph drop is about 1 point with co2 but theat is over a period of time,speaking only of non Discus tanks there is no harm in changing water in a co2 filled tank as the drop is only minimal have two hi tech tanks 40 and 45 with full pressurized co2 and for the last 6 yrs. have had no issue with that situation.As for a Discus tank I was talked out of co2[and happy I was] as a precaution and just to keep things as simple as possible but I see no problem with a slight ph drop.When changing water in a large tank the drop is probably going to be closer to .5 of a point...

  3. #3
    Homesteader Filip's Avatar
    Join Date
    Sep 2015
    Location
    Macedonia-Europe
    Posts
    3,639
    Real Name
    Filip

    Default Re: CO2, pH, and water changes

    To achieve an optimal amount of 30 ppm of Co2 in your water column you need to drop your PH to a 1 point (i.e. from 7 to 6 )and that happens in an hour to two when the Co2 is turned on .
    You need to repeat that 1 point PH drop/raise in a matter of an hour or two twice a day when lights and Co2 turns on and off every day . That alone beats the concept of pH stability and it becomes a matter of testing the resistance of discus immune systems on the long run .

    Sudden PH raise during WCs only adds up to the PH instability in Co2 injected tanks and the less frequent and severe the changes are , the better for your discus .

  4. #4
    Registered Member kilnakorr's Avatar
    Join Date
    Jan 2016
    Location
    Denmark
    Posts
    166
    Real Name
    Casper

    Default Re: CO2, pH, and water changes

    Just do your WC before CO2 is added on any given day. Adding CO2 and the remove with a WC is waste of CO2 anyway.
    Also, the 1 PH change doesn't equal 30 ppm CO2. It depends on other factors 😊

  5. #5
    Homesteader Filip's Avatar
    Join Date
    Sep 2015
    Location
    Macedonia-Europe
    Posts
    3,639
    Real Name
    Filip

    Default Re: CO2, pH, and water changes

    Quote Originally Posted by kilnakorr View Post
    Just do your WC before CO2 is added on any given day. Adding CO2 and the remove with a WC is waste of CO2 anyway.
    Also, the 1 PH change doesn't equal 30 ppm CO2. It depends on other factors ��
    How do you measure your Co2 level Casper ?
    Is there any other, more accurate way than pH drop measuring or using drop checkers which are basically pH drop meters too ?

  6. #6
    Registered Member
    Join Date
    Sep 2015
    Posts
    58

    Default Re: CO2, pH, and water changes

    i have a 240 gal planted tank with C02 injection for 8 hrs per day , 7 hrs. of light .
    i never saw a change in their behavior because of the c02 as a matter of fact this week 3 pair had wigglers out of 7 discus
    i think that healthy fish is a best starting point and ph. is in my opinion not that important , i don't even check it , in the past i did and it went up and down .5 deg. maybe a bit more when i did a massive water change .
    in my opinion the PPM. it a bigger influence .

  7. #7
    Registered Member kilnakorr's Avatar
    Join Date
    Jan 2016
    Location
    Denmark
    Posts
    166
    Real Name
    Casper

    Default Re: CO2, pH, and water changes

    Quote Originally Posted by Filip View Post
    How do you measure your Co2 level Casper ?
    Is there any other, more accurate way than pH drop measuring or using drop checkers which are basically pH drop meters too ?
    PH meters will show any change in PH a drop checker only shows a PH change in gas. If you have anything in the tank that could raise or drop the the PH meters will detect it but not the dropchecker.
    If yiu check the PH-KH-CO2 charts and look at the lower and higher KH values you'll see that 1 PH drop isn't close to 30 ppm of CO2.

    Example:
    PH 7.8 and KH 3 = 1.5 ppm CO2
    PH 6.8 and KH 3 = 14 ppm CO2

    PH 7.8 and KH 15 = 7 ppm CO2
    PH 6.8 and KH 15 = 70 ppm CO2

    For most people a PH drop of 1 is a good start. But, I would add the dropchecker and keep a close eye one the fish - the fish will certainly let you know when the CO2 is getting to high

  8. #8
    Homesteader Filip's Avatar
    Join Date
    Sep 2015
    Location
    Macedonia-Europe
    Posts
    3,639
    Real Name
    Filip

    Default Re: CO2, pH, and water changes

    Ive been away from Co2 use in my discus tank for a couple of years and back then when I used to read this, the chart and drop checkers were the best way to determine Co2 levels in the water .
    The latest literature from Denis Wong and Tom Barr though , tend to think that those methods are outdated and not completely accurate and offer the pH drop as the best way to determine Co2 levels in water .
    Here is a link from Wong's site on Co2 fine tunning methods :

    https://www.advancedplantedtank.com/...co2-level.html

  9. #9
    Registered Member kilnakorr's Avatar
    Join Date
    Jan 2016
    Location
    Denmark
    Posts
    166
    Real Name
    Casper

    Default Re: CO2, pH, and water changes

    Quote Originally Posted by Filip View Post
    The latest literature from Denis Wong and Tom Barr though , tend to think that those methods are outdated and not completely accurate and offer the pH drop as the best way to determine Co2 levels in water .
    Thanks for sharing.
    The first subtitle says "RELATIVE pH DROP METHOD POOR APPROACH".
    ​Test water for pH value, test water for KH value, then find corresponding stated CO2 level.

    This is an incorrect approach because many other factors can contribute to the tank's pH value; fertilisers, tannins & other chemical reactions.

    It seems the conclusion is the plant growth will tell you
    I guess this also requires your flow is good and surely all other parameters.
    Nothing is simple in the aquarium hobby.

  10. #10
    Homesteader Filip's Avatar
    Join Date
    Sep 2015
    Location
    Macedonia-Europe
    Posts
    3,639
    Real Name
    Filip

    Default Re: CO2, pH, and water changes

    Quote Originally Posted by kilnakorr View Post
    Thanks for sharing.
    The first subtitle says "RELATIVE pH DROP METHOD POOR APPROACH".
    ​Test water for pH value, test water for KH value, then find corresponding stated CO2 level.

    This is an incorrect approach because many other factors can contribute to the tank's pH value; fertilisers, tannins & other chemical reactions.

    It seems the conclusion is the plant growth will tell you
    I guess this also requires your flow is good and surely all other parameters.
    Nothing is simple in the aquarium hobby.
    Yes Casper. in some other readings from Wong I have found that good circulation and heavy surface aggitation (gas exchange and heavy oxigenation) are very important in succes with keeping healthy fish and high co2 levels at the same time . The more Oxigen In the water the better tolerance our fish will show for higher Co2 levels in the water .
    Some High tech people find Twinstar and Chichiros Doctor electrolytic units very useful in maintaining high oxigen levels (9-10 Ppm )and that raises fish tolerance on Co2 in the water so that they can put even more Co2 without having their fish gasping for air .

  11. #11
    Registered Member kilnakorr's Avatar
    Join Date
    Jan 2016
    Location
    Denmark
    Posts
    166
    Real Name
    Casper

    Default Re: CO2, pH, and water changes

    I've never liked the haze from those twinstar / doctors.
    But you're right; A lot of people refrain from to much surface agitation to avoid CO2 from escaping.
    However good surface agitation allows for more CO2 being injected.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Cafepress