Problems testing nitrates

[talieandsasha]

I'm cycling my tank (fishless) and at the point where I am testing nitrates, and I am getting varied results even a few minutes apart. For example, today I tested it at it looked like it was at 30, meanwhile my ammonia had dropped to .5 overnight so I added more ammonia, and then tested nitrate again because the 30 seemed lower from when I last tested it. well nitrate was now even lower, has this happened to anyone else? Is it possible that testing nitrate not long after adding pure ammonia will alter the results? Should get a new nitrate test kit? It's the API test and expires in 2017..

 

[Sk3lly]

Without sounding condescending, your probably performing the test incorrectly. The nitrate test is really important to follow the api instructions exactly

 

[talieandsasha]

Don't worry, no offense taken... lol I was SURE it was me doing something wrong, I did the test 3 times and kept reading the instructions, I even had my boyfriend to the test in case it was me... but still nothing consistent I'll probably ask to borrow my friends test kit (she has a diff. brand) and see what happens...

 

[Sk3lly]

Don't worry, no offense taken... lol I was SURE it was me doing something wrong, I did the test 3 times and kept reading the instructions, I even had my boyfriend to the test in case it was me... but still nothing consistent I'll probably ask to borrow my friends test kit (she has a diff. brand) and see what happens...

Ok as long as you shake bottle 2 VIGOROUSLY for 30seconds before you add the drops. Then after adding the drops shake the vial VIGOROUSLY for a minute.

If this is how you perform the test then im fresh out of ideas. Sorry

 

[talieandsasha]

yeah that's we do, I called my aquarium store and the manager said it could be pure ammonia that I added prior, but also could be a bad test bottle.. we'll see tonight, I'm going to borrow my friends

 

[threnjen]

the manager said it could be pure ammonia that I added prior

No... ammonia does not have nitrates in it. I don't know why he would say that.
How different do they look to you?
Did you give bottle #1 a couple shakes - you don't need to shake it a ton like bottle 2, but just a few shakes to make sure all the solution is well distributed. I've gotten bad results before from API tests when I didn't mix the solution before using.

 

[talieandsasha]

I usually shake each test bottle a bit (even for ammonia etc) so I'm pretty sure I did today as it's out of habit now, so I'm really not sure why it would do that I'll test it again tonight making sure to shake bottle1, invert tube several times, shake bottle2 30 seconds and the whole tube 1 minute... wish me luck

 

[talieandsasha]

Sorry, 1st test showed 30ppm, 2nd test showed around 10 and the 3rd stayed at 0...thats when I knew I either did something wrong or test is just no good...

 

[cfosgate]

I would try your friend's test just as a second source. If it's different then perhaps you should purchase a new nitrate test kit. You could have received a poorly quality controlled batch.

 

[talieandsasha]

I brought water to my friends house and we tested all parameters (ammonia, nitrite, nitrate) and indeed the nitrate was over 80 on her test kit, mine was showing between 0 and 5. The other parameters all matched so I will be going to buy a new nitrate test.

Thanks for all your advice!