Re: Aquatic Plants Digest V6 #79

[Paul Krombholz <krombhol at teclink_net>]

>     * From: "Tbarber" <terbarb at alltel_net>
>
>
>
>1.  Are the CO2 values the saturation values in water at the given
>conditions?

The amount of CO2 in water at saturation depends on the amount in the 
air.  Saturation with ordinary atmospheric air (0.03% CO2) gives you 
very little CO2 in the water.  Most aquatic plants would grow faster 
with more.  Saturation with an atmosphere of 100% CO2 would be way 
off the chart and would kill everything.

The chart is just telling you what the amount of CO2 is, given your pH and KH.


>2.  How do you know that you are putting enough CO2 into the system to reach
>the saturation point?
>
>3.  Does KH in the chart refer to "carbonate hardness" (alkalinity due to
>carbonates) not TA total alkalinity?


KH refers to total alkalinity.  It is determined by measuring how 
much acid you have to add to lower the pH to 4.2 The process measures 
the buffering capacity of your water.  That measures, roughly, how 
much stuff there is in your water that reacts with acid.

>
>4.  Can you recommend a test kit for TA - total alkalinity?


The little Tetra kit that measures GH and KH is quite adequate for 
most purposes.  GH, by the way, is a measurement of the amount of 
calcium and magnesium in the water.





-- 
Paul Krombholz in central Mississippi, being bombed by a thunderstorm.