Great article about CO2

[dpatte]

Just read this. Has anyone here tried drop-checkers?

http://www.practicalfishkeeping.co.uk/content.php?sid=5264&utm_source=PFK_newsletter&utm_medium=email&utm_campaign=September_21_2012&utm_term=CO2:_Striking_the_balance&utm_content=html

[exv152]

Interesting article, there are a few good pointers in it that obviously come from an experienced perspective. The only thing I would caution about is the use of the KH/PH chart method. The article doesn't talk about it but those who have more experience  with co2 will tell you it's not the best thing to use. The effect of any number of buffers in the water column will throw the results off, misleading you to believe there is more co2 in the tank than there really is. I highly recommend the use of a drop checker instead, or two is even better so you get readings from both sides of the tank, which you will notice can still vary slightly.

[charlie]

Interesting article, there are a few good pointers in it that obviously come from an experienced perspective. The only thing I would caution about is the use of the KH/PH chart method. The article doesn't talk about it but those who have more experience  with co2 will tell you it's not the best thing to use. The effect of any number of buffers in the water column will throw the results off, misleading you to believe there is more co2 in the tank than there really is. I highly recommend the use of a drop checker instead, or two is even better so you get readings from both sides of the tank, which you will notice can still vary slightly.

Actually he does caution about it & yes  it is not reliable

However, we may misread our test kits, or they may be inaccurate.  Liquid pH test kits rely on interpreting a colour chart and KH test kits rely on counting the amount of test kit liquid drops it takes to change the colour of the aquarium water in the test tube.

If either parameter is misread or inaccurate by as little as 0.2 pH or 0.5 KH it can mean under or over readings.

It's possible to think you are reading 30ppm CO2, but it could be as much as 45ppm or higher and lethal to fish.

Another factor can throw CO2 accuracy. The pH/KH/CO2 relationship assumes that carbonic acid from CO2 is the only acidifying compound, but this is not the case for most of us.

Nitric acids, humic acids and other organic matter will all contribute to acidification of aquarium water. This will typically result in pH readings lower than the table assumes — resulting in a false CO2 calculation.

[dpatte]

So, where do people get drop checkers?

[exv152]

Online is your best bet. There are no aquarium stores in town that offer the glass drop checkers. That I'm aware of anyway. The red sea drop checker is another one some use, those can be found a BAs.