LaMotte versus Aquarium Pharmaceuticals NO3

["Tom Wood" <tomwood2 at flash_net>]

I just did yet another comparative test after making a known dose from a
known starting point, using both test kits when they reported a 0 ppm start
point. After the dose, the LaMotte kit reported a value somewhere around 15
ppm. Since the color octet didn't match 2 or 4, I had to interpolate to 3,
and then multiply by 4.4, as required by the test. The Aquarium
Pharmaceuticals kit reported a value somewhere between 10 and 20, depending
on how you see it. The information reported by each kit is qualitatively the
same for my purposes. LaMotte - $40 plus for 20 tests. AP - $6 for 50 tests.
My advice - Go to Petsmart, buy the AP test kit, and see the movie 'Eight
Legged Freaks' for advice on anal fixations.

BTW, the Gladd calculator at:

http://www.csd.net/~cgadd/aqua/art_plant_dosage_calc.htm

said I should have had about 10 ppm NO3 after making the dose. Close enough.
The difference is inconsequential and probably due to the variation in color
rendition of the human eye.

This is not rocket science. Exact measurements are not needed. Close enough
is close enough.

TW