Nitrate Test Colour Wasnt On The Chart?

[manutd4life]

did a nitrate test today and it came back nearly clear!

anyone no what this is about?

did a 50% water change as my nitrite was quite high

 

[waterdrop]

What test kit? They use different reagents with different expected color scales. Also, what is the context? Have you been in the nitrite spike ..etc.?

 

[Curiosity101]

I think the second question would have to be...did you read and follow the instructions exactly?

And have you checked the expiry date on the kit...

 

[RadaR]

Nitrate test kits are notoriously innacurate.

 

[manutd4life]

i used the api master test kit, it isnt out of date and i always read the instructions and follow them.

i havn't added anything in the water!

its normally 0ppm

 

[manutd4life]

think i may have tested it incorrectly as its showing up today!

 

[MewMew42]

sometimes if the test tube hasnt been washed properly out you can get some pretty weird results!

 

[JoshuaA]

If its the API test kit make sure you shake the 2nd bottle vigorously for about a minute (at least), if not it comes out in a very running consistency and you're result will be either 0ppm or a weird colour. If you shake it enough it mixes well enough and you can get a real result.

I often though have difficulty judging whether my tap water is 0 or 5ppm of Nitrate. Sometimes I can shake the bottle like mad and get 0ppm and the next day I'll get 5ppm. Or my water supply can vary a lot in 24 hours

 

[waterdrop]

Agree with Mew and Joshua, I keep a bottle of distilled water which I can use to rinse a testtube before using it in a test. I normally just rinse with tap water but if feel there's a question I use the distilled rinse.

The problem with the 2nd reagent bottle in the API nitrite is very real. A component of the reagent will precipitate out while the bottle sits on the shelf and the precipitate can then "stick" in the bottom of the bottle or pieces of precipitate can clog the dropper neck. I always hold the bottle by the cap, before removing it, and swing the little bottle like a hammer, whacking the bottom corner against a bookcase shelf or some other hard surface edge (the idea being to break any precipitate loose from the inside surfaces of the bottle.) The shaking periods are a minimum, meaning you can shake even a bit longer.

In discussion with a chemist, I found out that tests to measure nitrate(NO3) are known to be notoriously difficult, no matter what level they are done on. Even with fancier equipment and techniques the results are not guaranteed to always be consistent.

~~waterdrop~~