I added more PMDD to the 5 gal tap water to bring the nitrate level to
10ppm. once again I read no nitrates in the water. so I added about 6
granules of stump remover to the 5ml test tube and added tap water. I then
tested this solution. Again no nitrates. This should have been through the
roof.

Is grants stump remover truly potassium nitrate? The label says contains
potassium nitrate. The MSDS list it as 98% potassium nitrate, although they
do not list what the other 2% is.

Why won't the test kit read any nitrate?

Scott


"Scott Rogahn" wrote in message
...
I have made my first batch of PPMD using the recipe at

http://www.nfis.com/~hartland/aqua/pmdd.htm

I used Grant's Stump Remover for potassium nitrate, Epson salt for
magnesium
sulfate, and sulfate of potash for potassium sulfate. I did not use the
Chelated Trace Element Mix. However I do use Flourish Iron and Trace.

My Nitrates are at zero both in the tank and out of the tap, measured with
an aquarium pharmaceuticals nitrate test kit. The kit reads from 0 to 160
ppm with the lowest colors being 0, 5, and 10ppm. Not the best resolution
for low levels but its what I have.

Using the calculator at

http://www.csd.net/~cgadd/aqua/art_p...osage_calc.htm

I determined it would take 8.5 ml of PMDD to raise the nitrate level of
tap
water to 5ppm. I added this does to a 5 gals of aging tap water before
bed
and tested in the morning. The nitrates were still at 0ppm.

Is something wrong with my PMDD, test kit, or my math?

I do not want to start adding nitrates to the tank in any large amouts
until
I know I can measure and control them.

Thanks
Scott