The KH is consumed to an extent with all filters. The bacteria use the
carbonates to help with the digestion/conversion of ammonia to nitrite,
giving off a Hydrogen ion, and then in the conversion of nitrite to nitrate,
2 Hydrogen ions are given off. These hydrogen ions are acid and they use
the carbonates to neutralize the acid and convert the hydrogen ions with CO3
to CO2 and water. The pressurized filters, bead filters are generally
associated with heavier fish loads than the garden pond with smaller
filters, and therefore more food to be converted, more acid, more demand for
carbonates/bicarbonates to prevent a pH crash.

--
RichToyBox
http://www.geocities.com/richtoybox/index.html
"~ jan JJsPond.us" wrote in message
...
On Mon, 16 Aug 2004 02:14:47 GMT, "Crashj"
wrote:

Is that because of the new water you are putting in each time you flush,
or
something else? Do you have to add dechlorinator?

The reason for adding Baking Soda? No, not because of the new water, (and
dechlor. is always wise when adding new) but something about the
pressurized system itself, beats the KH right out of the water. I'm sure
it
is a chemistry related thing, but I can't tell you what or how.

I did send this question into the chemistry expert on the KHA board, so
I'll let you know. ~ jan


~Power to the Porg, Flow On!~