[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: (Joe Reiter asked about....

Paul wrote:

Right.  The misunderstanding
above is unfortunately very common, and is to be found in textbooks.


You must almost feel like giving up on this one. Every rift lake cichlid
keeper believes that you cannot get CO2 to disolve in hard water. One of
the best known internet sites devoted to Rift lake Cichlids even has a
chemical formula that indicates that the solubility of CO2 decreases
when water contains high levels of carbonate and therefore you cannot
disolve CO2 in high carbonate water. If this were true the oceans would
be in big trouble I think.

There are other reasons why this is widely believed. I think Rift Lake
Cichlid tanks are often filled with calcite rocks or coral. When you
inject CO2 the calcite disolves and raises the KH. It makes it look like
the CO2 didn't disolve. Another reason is that a lot of pH test kits
don't work well over the range required to actually see the pH drop.