Issue Reading Nitrate Test >.<

[NewToFish1989]

I love API's fresh water master test kit but the Nitrate test frustrates me more than anything and is the most annoying to read. Tested my water today and test against the card says 40ppm, thought that can't be right, only did a weekly water change yesterday. So put brightness of my computer screen super bright and used that and then read 5-10ppm >.<

What's the best method to read this test? Ph, Ammonia and Nitrite are easy, just Nitrate is annoying me.

 

[Khuligirl93]

What works best for me is to be in a room with natural light, and make sure you hold it against a white background. I will admit though, I always have had trouble distinguishing between the 10 and 20 ppm colors.

 

[sodbuster95]

I agree with Khuligirl93 on using natural light. The color charts for the API test kit have, at times, made me wonder if I'm color blind. I've found that the best way to read them is with lots of natural sunlight. Failing that, incandescent light is the next best. In my experience, fluorescent and LED light (which is what your computer is probably using to backlight the screen) alters the color too much and makes things worse.

 

[DownDogKate]

I have that same frustration. I've even asked 2nd and 3rd opinions around the house. Bright natural light I figured I out, but do you place the vial on the card to there's full contact with the card or just hold it up close? The colors are very different. Sometimes I can't figure out if my reading is at 80 or 20!

 

[sodbuster95]

I have that same frustration. I've even asked 2nd and 3rd opinions around the house. Bright natural light I figured I out, but do you place the vial on the card to there's full contact with the card or just hold it up close? The colors are very different. Sometimes I can't figure out if my reading is at 80 or 20!

I hold the vial near, but not against, the card. Holding it right against the card seems (to me) to shadow the color, changing it's appearance.

On some of these tests, it's really just a guess between two (or three) close colors. The pH test, for example, has driven me to distraction of late and I've taken to using the pH test kit I have for my pool from Leslie's Pool Supplies. The test vial is a square plastic tube with the color embedded in translucent plastic right next to the view chamber. You can far more easily compare the colors regardless of light. The downside is that the resolution is .4, so I'm still guessing within +/- .2.

 

[DownDogKate]

+1 to reading the ph. too high for the low test and seemingly too low for the high test. I figure as long as it's consistent I'm ok.

 

[rpgmomma8404]

I bought a used test kit that didn't come with the cards (think the people I bought it from threw them away) so been using pictures online. I just take a lucky guess on it. I've gotten it down to knowing what colors should be okay for my tanks and when stuff is too high. I do water changes twice a week and that has helped with bringing my nitrates down greatly.

If I am unsure about my water. I take it to a mom and pop pet store that also uses liquid test to double check. So far everything has been fine.

 

[DownDogKate]

True. If you step back from trying to get exact numbers, you can generally see when you need an extra pwc. Can't help but want to know those exact numbers though!