[Djbetterly]

So I tested my water tonight and here are the values:

KH - 5
pH - 7

That yields a CO2 level of around 12. When I measured my KH and pH about three days ago the KH was 3 and pH 6.5 which gave me a CO2 of around 28.

Is this a good or bad shift? Ideally I'd like my CO2 to be a bit higher of course. Do I let things be and see what happens? Water change? Add more CO2? Any help is appreciated!


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I am here: http://maps.google.com/maps?ll=40.782098,-73.954870

 

[Hoppy]

Measuring pH and KH will not tell you how much CO2 is dissolved in the water, unless you are using pure water (distilled) with nothing else in it that affects the pH except carbonates and CO2. If you use a drop checker to measure the CO2 you can at least know that you are somewhat near an effective level of CO2 in the water.

 

[Djbetterly]

I'm very confused then. All of these forums say to use a chart to figure out your CO2 levels by means of KH and pH levels. What is the difference between the number you get from the chart versus a CO2 drop checker?

 

[Hoppy]

If you use a drop checker correctly, you will put 4 dKH water, made from distilled water and a bit of baking soda, in the drop checker "bulb". To that you will add 2-3 drops of pH reagent, one that is yellow at about pH 6, and blue at pH 7.2. That will be water with nothing in it that affects pH except carbonates and CO2. And, that makes it as accurate as you can get with the pH/KH/CO2 chart. Typical tank water will contain several substances that also affect the pH, so the chart is useless with that water.

Just because "everybody" says something, doesn't mean it is correct. "Everybody" used to say that fertilizing can cause algae. "Everybody" used to say that 2 watts per gallon is good lighting. "Everybody" often still says that aquatic plants out compete algae for nutrients. Etc. "Everybody" talks a lot:icon_mrgr

 

[R_Barber001]

If you use a drop checker correctly, you will put 4 dKH water, made from distilled water and a bit of baking soda, in the drop checker "bulb". To that you will add 2-3 drops of pH reagent, one that is yellow at about pH 6, and blue at pH 7.2. That will be water with nothing in it that affects pH except carbonates and CO2. And, that makes it as accurate as you can get with the pH/KH/CO2 chart. Typical tank water will contain several substances that also affect the pH, so the chart is useless with that water.

Just because "everybody" says something, doesn't mean it is correct. "Everybody" used to say that fertilizing can cause algae. "Everybody" used to say that 2 watts per gallon is good lighting. "Everybody" often still says that aquatic plants out compete algae for nutrients. Etc. "Everybody" talks a lot:icon_mrgr

Couldn't agree more! After reading a thread that I find interesting I keep reading to verify that information. The chart is perfect!!! 'small print' for distilled water.... Well played Hoppy!

 

[Hoppy]

I think my comment above was a little harsh. One thing not to lose sight of is that most of the stuff that "everybody" is sure is correct was believed by virtually everybody at one time or another. And, a lot has been learned over the past 20 years or so, that has made much of what we all were sure was correct incorrect. I'm even pretty sure that the coming years will continue to make things we (I) believe today incorrect. A big part of the excitement of this hobby is how we all continue to learn more, refining our methods, and gradually making a success in the hobby accessible to more and more people. But, if only "everybody" would learn that more light is very often worse light things would go much better..........