[Coral-List] RE: NH4 Levels In Aquaria

[Stephen Lowes]

With reference to NH4 Levels in Aquaria (Steve Lowes)

Dear Coral List:

Julian makes a good point to the "potential" benefit of dosing ammonia to
stimulate strong coral growth. I can add that I am currently experimenting
with this in the aquaculture of Pacific scleractinian species. Following a
guideline offered by Jorg Kokott (Coral, Vol 2 No 1, p68 2005) I am dosing a
250 mM stock solution of ammonium chloride to a fully matured, closed, coral
propagation system. I am only doing so to the extent that I raise the
nitrate levels in the system from undetectable (< 0.25 ppm) to approximately
1 ppm. Ammonia and nitrite levels remain undetectable using colorimetric
aquarist test kits. I am also employing several mechanisms of nitrification
including sand beds so without daily dosing the nitrate level is quickly
reduced to undetectable. Together with herbivores I am able to control
nuisance algae growth. 

I do not pretend that the above is a rigorous scientific approach but I am
looking to try and quantify the coral growth rates across species. Since we
are dealing with a multi-variable dynamic system it is always going to be
difficult to get a categorical handle on quantifying the effects of a dosing
protocol of this type. Assuming that increased growth rates could be
demonstrated, it would be interesting to determine if this is from the
corals use of ammonia or the oxidized products (nitrite and or nitrate).
Only other info that I can offer to this interesting thread is reference to
the paper - Titlyanov et. al. Effects of dissolved ammonium addition and
host feeding with Artemia salina on photoacclimation of the hermatypic coral
Stylophora pistillata Mar. Biol. 137: 463-472 (2000).

Steve