How do I know my CO2 levels?
- Thread starter anniecox
- Start date
tanker
Josh Holloway--Be mine!!!
I went online to check out CO2 testing stuff. Looked under drop checker. CO2 test kits, etc. Not much listed. Found one Tetra Freshwater kit that had a CO2 chart (?wondering what that is??) Nothing else. Nothing listed as a drop checker. Any recommendations of a brand, how it would be listed, etc? Hoping not too costly. thanks.
I use the Tetra Test Laborett kit that has the KH solution. The chart is used to see what your Co2 levels are by using your pH value and your KH value. The KH is measured by putting drops into the vial and counting how many drops it takes for the water to turn from blue to yellow. Fairly simple. I can't remember how much the test kit cost and I am not sure if you can buy the KH solution seperately. I am sure you can, just not sure where.
I bought some DC's on Ebay and some certified 4KH & indicator solution from Greenleaf.
I'm somewhat disappointed with the setup.
I started a thread about CO2 levels indicated on the color chart.
The three colors are blue which indicates low CO2, green which is 30ppm
(must be an estimate), and yellow which is high CO2.
I can actually get a closer CO2 reading using my test kits and a CO2 chart.
Some answers on that thread said that there are other factors which cause a faulty CO2 reading and 4 KH with a DC is more accurate.
But blue being not enough CO2 and yellow being too much CO2 is not very accurate in my line of thinking.
Also, the GLA indicator solution does not turn the 4 KH dark enough for me to check it in the tank. I have used 6-8 drops and it's not dark blue at all.
I still use the 4 KH but I went back to the cheap indicator solution that came with the DC's.
Charles
I'm somewhat disappointed with the setup.
I started a thread about CO2 levels indicated on the color chart.
The three colors are blue which indicates low CO2, green which is 30ppm
(must be an estimate), and yellow which is high CO2.
I can actually get a closer CO2 reading using my test kits and a CO2 chart.
Some answers on that thread said that there are other factors which cause a faulty CO2 reading and 4 KH with a DC is more accurate.
But blue being not enough CO2 and yellow being too much CO2 is not very accurate in my line of thinking.
Also, the GLA indicator solution does not turn the 4 KH dark enough for me to check it in the tank. I have used 6-8 drops and it's not dark blue at all.
I still use the 4 KH but I went back to the cheap indicator solution that came with the DC's.
Charles
Since CO2 forms carbonic acid when it is diffused in water, it will drop the ph of your water. To figure out the CO2 concentration you take a water's ph level (acidity) and compare it to the kh level (buffering capacity), this would be the chart that you see. This method is only accurate if CO2 is the only acid present and calcium carbonate is the only buffer, which is never the case in an established tank.
So what is a drop checker? A drop checker is a container that separates an indicator solution from the tank water by an air pocket for gas exchange. As CO2 gas from the tank water diffuses into the air pocket it is absorbed by the indicator solution, which is a mixture of Bromothymol Blue (same stuff as ph indicator) and water with a 4dkh. As the acidity rises the color of the solution changes. In essence, the drop checker works with the same mechanics as the chart but rules out contamination by other acids or buffers. Since the drop checker works by color change, you won't get an exact reading but you don't need to have an exact CO2 level, just know that blue is too little, green is good, and yellow is too high.
So what is a drop checker? A drop checker is a container that separates an indicator solution from the tank water by an air pocket for gas exchange. As CO2 gas from the tank water diffuses into the air pocket it is absorbed by the indicator solution, which is a mixture of Bromothymol Blue (same stuff as ph indicator) and water with a 4dkh. As the acidity rises the color of the solution changes. In essence, the drop checker works with the same mechanics as the chart but rules out contamination by other acids or buffers. Since the drop checker works by color change, you won't get an exact reading but you don't need to have an exact CO2 level, just know that blue is too little, green is good, and yellow is too high.