Testing confusion and troubles...

So, like most of you guys here, I use the API master test kit... When I use this site to check my parameters it yeilds different results than using the comparison chart... I feel like the site is mote accurate, but I'm not sure... I always thought my tank was processing 3ppm ammonia in a day but when I hold the vile up to my phone light next to the comparison chart, it says its between 0.25 and 0.50

When a tank is fully cycled you would not detect any measurable amount of ammonia. So is this a new tank setup?
In any case, you hold the vial against the white background of the card as natural (or phone) light will reduce the color in the vial.

Agree with above. Also, the "light" that you use to read the colour is very important. Always use natural diffused daylight, which means daylight but not direct sunlight. Natural daylight will render a true colour rendition which I have found makes it much easier to read the result. All artificial light, whether incandescent, fluorescent, or LED will distort some colours, more or less depending, and are unreliable for colour tests.

Most tests are best read with the phial held in front of the white card, and next to the colours on the card. The GH and KH tests of API can sometimes be difficult to read but with these it is best to look vertically down into the tube over a white background (the tube standing on white), you can readily detect when it first changes from orange to green, or whatever.

Thank you! This helps out a lot!

I find API chart matching difficult, and the lack of gradient in some cases makes it worse. I believe some of my trends/variances in nitrate are just due to the inability to properly interpolate given the similarities of some of the colors. There is also the issue of where to hold the vial WRT the card. I believe API has stated (not on the instructions but in reply to users questions) that the vial should touch the card.

I wonder if you could run the Nitrate test in two 5ml samples using half the indicator solution in the second vial. This should (assuming all things linear) result in an indication of 50% of the actual ppm in the second vial. You could then see which two colors best match up with high/low vials, using either the high value or 2x the low. This would be most useful for differentiating between 20/40 ppm NO3. Anything less is generally readable, and anything more is way to much NO3 and needs to be dealt with. It might still be nice to know the value at the high end if you were concerned about osmotic shock and wanted to do several smaller WCs over a day or two. I'm still relatively new to the nuances of the Nitrogen cycle so this is just an idea submitted for the experts here.

It might work... But it just seems like too much trouble

Rocky998 said:

It might work... But it just seems like too much trouble

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Yeah, but for some odd reason I enjoy it. I've also enjoyed creating a calculator that predicts levels based on water change amounts, frequency, and contaminant build up rates. Weird, I know ...

Yah, everyone has their things I guess lol... Thats just not one for me

Oblio said:

Yeah, but for some odd reason I enjoy it. I've also enjoyed creating a calculator that predicts levels based on water change amounts, frequency, and contaminant build up rates. Weird, I know ...

Click to expand...

Oblio said:

Yeah, but for some odd reason I enjoy it. I've also enjoyed creating a calculator that predicts levels based on water change amounts, frequency, and contaminant build up rates. Weird, I know ...

Click to expand...

awesome! Not weird at all!

Here is my prediction given my current nitrate, nitrate rate (5 ppm/week) , and a 50% WC/week.