I need help accurately reading API test kit
 

I've been cycling my tank for 4 weeks now and in 12 hours the bacteria are processing ~3.5ppm of NH3. I did a nitrite test for my tank using an Aquarium Pharmaceuticals test kit. When I was comparing the solution color to the chart in a well lit area I noticed that if I place the tube directly against the chart card the solution color is darker than if I allow space between the card and tube. This made the nitrite concentration reading be 2 ppm<n<5 ppm if the card was directly against the card and n=0.50 ppm if there was space between the card and tube. That's a big difference.

Should I be reading the tube away from the card or right against the card?

hello and welcome :)
not sure how everyone else does it,but i hold the tube to the card standing with the back door behind me with the natural light comming in.

thats how I do it too willow. I let the natural sunlight hit it

So to clarify, you put the tube right against the card?

Yes, that's the way I've always done it. And like the others said, have the light coming from behind you :-)

Yeah, I always have the light coming from behind. I don't have good access to natural sunlight from my dorm or bathroom so I just use the bathroom light which is sufficient.

you should be fine. :)
if i think the levels even look a little not right,i would do a water change.
seems to be working that way for me.

I tend to use fake light up against a white wall with the tube against the card. Apparently I'm not "right" but I seem to get pretty good results.

same here. i use the white of the card. i use my kitchen lighting and sometimes natural lighting. regardless my reading are pretty close. my tank is cycled so i know if the reading is where they should be. if it does look way off, i change the angle in which the light hits the bottle or retest. make sure you add the proper drops. if your not paying attention you could add more than intended.