Re: Nitric (Nitrous) & Sulfuric acid

> ------------------------------
> From: spush at saudan_HAC.COM
> Date: Thu, 06 Feb 1997 16:25:04 PST
> Subject: Nitric & Sulfuric acid
> I was wondering if nitric acid is a biproduct of the nitrification
> cycle or other chemical processes in the aquarium? The pH in
> my aquariums is quite low; lower than can be accounted for by
> CO2 injection. I wondered if this was due to humic acids or
> from the nitrification process. A much stronger acid, sulfuric
> acid, could that also result from the decay of organic material?
> How does one obtain long term pH stability in those aquarium systems
> where water is not changed regularly?
> Steve Pushak     spush at hcsd_hac.com      Vancouver BC Canada
> ------------------------------
	My understanding is that both nitric and nitrous acid are produced
during nitrification, and that they can contribute moderately to
acidification, depending on the Alkalinity of your water.  As you probably
know, we fight the same soft water = rapid acidification problem here in
Seattle, but i've found that the Dolomite I've been adding for the sake of
my swords (thanks for the posted tips on Ca deficiency in swords, btw) has
kept my tanks' pH pretty stable.  The KH in them is now about 4 or 5.  In
fact, in my tanks up in Canada (Abbotsford) I rarely had a pH drop
problem, because their water also has a KH of 4 or 5, unlike the
neighbouring Clearbrook, with 0 to 1 KH. 
	As to sulfuric acid, I don't see it happening, although
hydrosulfuric acid is a possibility, since it would be the result of
Hydrogen sulfide with water.  I'm not sure how powerful an acid it is.

	And now a question for you (well, actually 2 questions ;-): Are
you using just CaCO3, or are you too using Dolomite?  If the latter, how
do you find the additional Mg affects the nutrient balance for your
	If one has a laterite or similar substrate, is adding more iron
really necessary, or could it be left out of a PMDD?