Re: Low pH nitrification THE ANSWER?

["JAY SIDERS" <tas3@flash.net>]

----------
> From: WndrKdnomo@aol.com
> To: apisto@majordomo.pobox.com
> Subject: Re: Low pH nitrification  THE ANSWER?
>
>   I would love to take issue with what was earlier posted.
> 
> In a message dated 10/21/98 5:09:54 AM, IDMiamiBob@aol.com writes:
>   
> << Not all the ammonia converts to
> NH4+.  that which is still NH3 would get metabolized.  As soon as it is
gone,
> NH4+ ions would convert back to NH3, in an attempt to achieve "stasis".  
I would love to see your reasoning for this. The fact is, if a tank is
balanced from the get go with a low pH, the nitrogen cycle bacteria which
will colonize the tank will process NH4 much better than NH3 as it will be
the predominant food source.  Further more, in a high pH tank NH4 is still
just as readily consumed as NH3.  Your assumption on that issue is wrong.
 >>
> 
> You are absolutely correct, in that there is an "equilibrium" between the
> ionized and unionized forms of ammonia.  Basically, as you indicate, this
> means that at a given pH a certain percentage will be in each form, NH4+
or
> NH3.  If you remove some of the NH4+, some of the NH3 will be ionized to
> maintain the equilibrium state.  This is true at ANY pH.  However, at
highly
> acidic pH values, the percentage of unionized ammonia that is
"bioavailable,"

 THIS is a mis nomer.  There are at least tweny straines of nitrifying
bacteria.  A few of which thrive at low pH and love the ammonium Ion.  Your
bio-chem books are going off of old research.  The key to balance  of
nitrogen cycle is consistant pH and tempurature.  Think about it.  If
bacteria could not survive at very low pH how do we get viniger?  Also,
when was the last time you checked pH at a sewage plant?  The water is
commonly very low pH and yet there is very little ammonia or nitrite
realeased into the local rivers and streams.
> if you will, is very, very low.  (My old biochem books are all packed up,
or
> I'd look it up).  Even if the ammonia reducing bacterium (and the exact
cast
> of characters in aquatic environments is still uncertain, see earlier
> postings) is still alive and active at low pH, the conversion of ammonia
to
> nitrite would be very much slower than at neutral pH.  At the same time,
the
> fish are producing ammonia/ammonium at the same rate, regardless of pH. 
Thus,
> you wind up in the same practical situation as if NO conversion was
taking
> place.  That is, even if you have some nitrate accumulation as the result
of
> Nitrogen Cycle activity, you 
     This would be true in a new tank or a tank dropped quickly to a low
pH.  But if you start the tank as acidic from the beginning, the right
microbes will develope to quickly reduce ammonia and nitrites.  Water
changes are still necessary, but concistancy of pH and temp are the keys.
may ALSO have a high concentration (relatively
> speaking) of ammonium ions.  In practical terms, this still means no
large
> water changes in highly acidic aquariums if your new water has an
appreciably
> higher pH.  This is only common sense, as you don't want to expose your
fish
> to large pH swings anyway.
>      As a further note, someone was wondering how a low pH tank could
function
> and not "crash" if no Nitrogen Cycle activity was occurring, I will
repeat
> what was said earlier. The ionized ammonium ion (NH4+) does not pass
through
> cell membranes (read "gills") and therefore is not take up by organisms,
and
> is not toxic to our fish. Therefore, it does not really matter if nitrate
or
> ammonium accumulates in our low pH tanks, as long as correct tank
maintenance
> procedures are followed.
  Of course ammonium is not as toxic to fish, but it is bothersom.  The
right bacteria take a while to culture but they will.  The longer the tank
is kept at the same temp and pH the more bacteria develope and the faster
the cycle rolls.  

How do I know this?  Tweny years of breeding angels and five of discus.  If
you don't believe me ask a real expert like Hoevanec at Marineland.
     The research is growing faster than you can possibly imagine.  
     If anything I suggest doing a little waste water treatment plant
research.  It will better help you understand the complexity of
bio-filtration.


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