How to use CO2 chart

[Elroy]

Hi all,

Im looking for some advice in how to use the CO2 chart. I just mesured the water in my tank. Readings say PH 6.8 and KH 11. If I look at the chart I attached (Not the best/most precise, but it was the only jpeg version I could find) I get a reading of +47,0. But +47 what? Bubbles pr sec or something else - maybe mg/l? Can someone explain how to use/read the chart, in order to get the right amount of CO2 (Bubbles per second)

Thanks Elroy

 

[Hufsa]

The short story is that you cant use this chart to directly find your CO2 level. Unfortunately the people who promote the use of these charts do not fully understand the mechanisms involved in a planted tank.
The chart is not technically wrong, its just that these charts assume that the only acid in the aquarium is from CO2. This works in a laboratory sample, but not in an aquarium, where decay and biological activity will contribute other acids to the water. Therefore the readings you get from such a chart will be misleading or directly wrong.

If you want to really get a good grip on your CO2 levels I strongly recommend to search for some of the forum posts that talk about doing a PH profile. This method gets around the issue of other acids in the water, and makes sure your CO2 level is stable, which is a very important detail. When you read the posts make sure you note the fact that the "base PH reading" must be taken from a degassed sample of aquarium water. This means a sample of water that has had all the CO2 escape from it. This way only the other acids will be left in the sample water, and we can then use it to determine how much our PH is dropping from only CO2.

Hope this makes sense

 

[Elroy]

Thanks for the answer. It makes sense , a bit I will drop the chart reading for now, and begin making a PH Profile.I found this

Dialling in the CO2 injection Rate and CO2 Profiles

Why do we need a stable Carbon Dioxide (CO2) level? A stable Carbon Dioxide (CO2) level or concentration is key to successfully growing plants in a CO2 injected tank. The CO2 concentration needs to be stable throughout the photoperiod, usually anything from 6 to 8 hours long, and consistent from...

www.ukaps.org

which I will start to read. Thanks again

Cheers Elroy

 

[Andy Pierce]

Getting a drop checker is pretty straightforward for a 'good enough for most purposes' measure of CO2 levels as well. Be sure you do NOT use aquarium water as the colour indicator solution in the drop checker.