Still being somewhat suspicious of the #'s I tried testing again tonight using a different test kit. The first were done with Salifert, so tonight I tried with Elos.
I suspect that the Elos kits strengths are in the lower ranges. I took two test tubes side by side and did the input and output water together. I had to stare at the colours for a long time before deciding that one did indeed seem "less pink" than the other. The only sorta downer is that the pink matches more like 75ppm and 50ppm.
I think I must be colourblind because I really have a heck of a time staring at pinks and trying to compare to the colour chart. They're all "fuscia" to me.
I talked to American Marine earlier today and I'm told that I'm the first one to call about any problems with their nitrate monitor. (Yay me! Go team!! Wooty!!
). Anyhow he gave me some suggestions but there really isn't a lot to work with (short of leaving the probe in the calibration solutions longer). The readings, if not clamped at over-range, are hugely fluctuating. For example tonight I got it to read anywhere from 30ppm to 100ppm to over-range on the 100ppm sample. I'm going to talk to them again tomorrow or Monday, hopefully we can get it working right or determine that it can at least be replaced if nothing else. I'd love to see what the readings are with something that can tell me real #'s as opposed to "in the neighbourhood of 50 to 75ppm".