Perhaps you have heard before about the CO2 drop checker. Or perhaps not, but it is quite probable that you did not get the full idea of what is telling you and how interpret it.
This article is thought to introduce this useful device to those who want to use CO2 in the aquarium and they do not know how to control its dosage of the tank. It will be also very useful to clarify how to read it, as well as discussing some of the most persistent questions about it.
Note that part of the discussion can become rather technical. I will try to keep it in reasonable levels, though, but I will include some sections that can be very tricky for those who have not been involved in Chemistry education. As a traditional seal of The Living Tank, I have decided to include that, so people can see this is not just "another interpretation" but just the valid interpretation that should be considered.
