Well. I just measured KH and it is around 5.5 thus according to the
chart you gave me link to it means CO2 was more than 100 ppm. But that
does not seem to be possible since all I was doing was spreading fine
CO2 bubbles with power head. Could it be that there were to many
bubbles? Power head was providing suction from DIY yeast reactor.

Dmitri Priimak

Szaki wrote:

As I heared adding CO2 can change the PH of the water, so you have to
monitor closly.
KH, pH, and CO2
The CO2 content of your aquarium is important if you are growing plants
(though check out a discussion on which plants need supplemental CO2, and
which may actually do worse with it!). But CO2 is also of interest to the
general aquarist because it is intimately related to the water's carbonate
hardness (KH) and pH; dissolved carbonates will raise both KH and pH, while
addition of CO2 will lower pH. Here are some charts showing the relationship
between CO2, pH and KH, along with a discussion of the actual chemical
reactions. You can read CO2 content indirectly by from the combined pH and
KH readings, from a good test kit, or try this simple metering method.

A few plants are able to take in carbon directly from dissolved calcium
carbonate (a procedure called biogenic decalcification by some). This
procedure in turn may cause your pH to rise.

You can easily make your own carbonate buffer from common chemicals. You can
use Calcium Chloride to increase GH without changing the alkalinity and pH.
Some suggest you can use hydrochloric acid in extreme moderation to reduce
the buffering capacity of your water (this article also discusses an
empirical result of CO2 content vs. KH).

http://www.thekrib.com/Plants/CO2/kh-ph-co2-chart.html



JS



"Dmitri Priimak" wrote in message
...

Hi All.

I am somewhat new to this hobby. And today I made CO2 system with yeast
and was injecting bubbles with the power head and pH dropped from 7.2 to
6.2 withing about 4 hours. Luckily I don't have fish in the tank yet.
So, why did it drop so much? From what I read I did not expect to
dissolve much of CO2 by just bubbling it though water. Is there anything
wrong with my water? Is the hardness somehow related to it.

--
Dmitri Priimak