Biogenic Decalcification

To: Aquatic-Plants at actwin_com
Subject: Biogenic Decalcification
From: DAWB.DSKPO33B at DSKBGW1_ITG.ti.com (David Webb)
Date: Wed, 31 May 1995 09:07 CST

>> Some plants, in the absence of enough free carbon dioxide in the
>> water, are capable of removing dissolved carbonates from the water to
>> provide their carbon needs.  Others can't.  This may also explain your
>> poor plant performance.  This is measurable as a drop in your KH.
>
>The term used in _The_Optimum_Aquarium_ and a few other resources is 
>"biogenic decalcification" and causes the pH to go UP not down.  

I looked in The Optimum Aquarium yesterday evening to freshen up my knowledge 
after reading this post.  I didn't see anything that said the pH specifically 
goes either way, just that the KH drops to near nothing, making your tank 
susceptible to rapid pH swings.

I can see situations based on this where the pH could either rise or fall, 
depending on other ions in the water.

David W. Webb
Enterprise Computing Provisioning
Texas Instruments Inc.
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