[APD] RE: high NO3

["Thomas Barr" <tcbiii at earthlink_net>]

Tomoko, 

I'd vacuum the substrate in 1/4 sections or even 1/2 sections each week
till clean. Deep vacuuming. Large water change. 
Next clean that filter media good in warm/cool water.

It is important to make certain the CO2 is good and double check the GH/KH
also(tap water might change or the sources used to supply the water line).
Fert routines are not the issue, it's something else... if the fert routine
is being done consistently.

Now my question is also this: why are you using the test kit rather than
your eyes to gauge the tank's need?
Was there really a problem prior? Or was it just a response to the test
kit's reading?

You can do larger water changes to reset the tank rather than a test kit
and time. 
Test kit readings do not tell you what you need to know often(Iron is a
good example), there is an inherent implied assumption that a measurement
is better for plants, often we test different things with a test kit yet
assume that the level is bad or good, when it's not.

I've always approached it from "is 1-2ppm PO4 really a bad thing?" (or
30ppm of K+, or high Trace dosing, 30ppm of NO3 or high CO2, or vacuuming
accumulation of mulm, or etc....).
 
While some may defend cheap test kits, I do not bother. Rather, I look for
other causes for the problem and know the plant's response's to NO3 dosing.
Micrantherum umbrosum is a good indicator plant for NO3. Bio indicators do
not lie and focus on what we need to know. I believe Amano does this as
well, I've yet to hear him mention or talk about testing. You would know
even better than I about that. Neither he nor I are big test kit proponents
in this hobby and arrived at this from independent directions.

Folks enjoy haggling with me on the issue of testing, yet:
http://www.sfbaaps.com/reference/barr_02_01.shtml
I did do this a great deal a number of years ago and still do in different
context today (with about 2000$ in test equipment and that's just my
personal stuff).

Now why would I and Amano tell folks to look at their plants, dose
accordingly, do large frequent water changes, turn CO2 off at night etc? Do
we want to mislead or keep secrets from folks?   

But follow the routine for cleaning, keep an eye on the plants, do a very
large, say 80% water change once in a while, then add the ferts right back
afterwards. That will reset things and wean you off the test kit readings
so much. Run a series of standards over the range in question when you
decide the test is telling you something you feel you should make a change
to.

I can tell you 2 weeks of not dosing KNO3 is bad with CO2 enrichment, the
organic fraction may be high from the substrate or dirty filter etc.

But the advice will address several things to fix the issue, the substrate,
the filter, the water(larger water change), the test kits, CO2/GH/KH and
the plants. That way you cover all your bases and switched from a large
organic component to inorganic bioavailable forms of plant nutrients.   

Regards, 

Tom Barr

subscribe at BarrReport_com           Get connected
www.BarrReport.com                    Get the information  


> I am puzzled about NO3 levels that I am getting from my test kits lately.
I 
> tested my water a number of times with relatively new Aquarium 
> Pharmaceutical's test kit and a brand new Salfert's test kit, and the 
> results are consistently high around 30 to 40 ppm.  I have been sticking
to 
> Tom Barr's recommendation on the tank maintenance and I never had a
problem 
> until this year (this tank was set up in 2000.)  I stopped adding KNO3
for 
> two weeks or so and the NO3 level dropped to 10 to 15 ppm range, but some
of 
> my plants look really nitrogen deficient now.  I think my fish load is 
> moderate (20 cardinal tetras, 5 harlequin rasboras, three or four
coridoras, 
> two SEA and a few more small tetras) for a heavily planted 75 gallon tank 
> (equipped with four 55W PC's and a pressurized CO2 system.)  I have not 
> changed fertilizing or fish feeding regimens over the 5 years.  Is it
time 
> to clean substrate (100% Fluorite) drastically or change out my 5 years
old 
> media in my Eheim 2026?  I cannot really figure out where my extra
nitrate 
> is coming from.  My tap water contains less than 5 ppm of nitrate (it 
> usually read 0.)
>
> Tomoko 



_______________________________________________
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com
http://www.actwin.com/mailman/listinfo/aquatic-plants