varied test results

[golum]

On the recommendations of members from this forum that not having a water testing kit is a sin
i bought a API FRESHWATER MASTER TEST KIT.
Now Ive done the tests for water parameters and some of my results varied.

PH: 7.6 - no problem
Ammonia: I did this test 3 times as to get a anomaly proof reading, now 2 of them were yellow which indicates 0 ppm while one of them looked more very pale green (0.25ppm)
i thought that maybe the one that wasn't 0ppm was a anomaly because the color was different. (2 results were 0ppm- one result was 0.25ppm)
Nitrite: i tested twice, first result was light blueish which was 0ppm but the second result yielded very light purple which is 0.25ppm. (one 0ppm-one 0.25ppm)
Nitrate: tested twice and results were dark reddish, id say about 40-80 ppm.

My theory is the odd one out results were anomalies were something wrong happened, because i am pretty sure my fish tank has cycled a while ago.
Because surely if i have 40-80ppm of nitrate that means the cycle has finished as that is a end product? for if i hadn't cycled my tank fully i wouldn't have that much nitrate because i did a water change under a week ago and i have plenty of live plants.
So my question is does it look like my aquarium has cycled? and should i be worried about these out of the ordinary results?
Much appreciated.

 

[1bigdovii]

I think your good. The results from any test kit IMO are ball park results and will never be exact. If your getting nitrate readings then you should be fully cycled.

Sent from my SCH-I500 using MonsterAquariaNetwork App

 

[quasar]

Like with any scientific test results can have slight variations, that's why you do more then one. If the majority were fine then I don't see a real reason to be alarmed. It's kinda like weighing yourself every day and getting mad that your weight shifted +/- 2 pounds. You should be more alarmed if in one week you decide to test again and you see a 20% change in the result parameters.

Sent from my Galaxy Nexus using MonsterAquariaNetwork App

 

[duanes]

Working as a water chemist/microbiologist for almost 20 years, I've learned if a tube was not thoroughly rinsed after testing, numbers could easily be skewed. We usually would toss the highest and lowest tests if a reasonable number in the middle were close.
It is always a good idea to pick up a little DI water to rinse your glassware, we always rinsed 3 Xs after each use.

 

[thebiggerthebetter]

I use the same test kit.

IMO, "cycledness" is determined by zero, or essentially zero, NH3 and NO2 (regardless of NO3 readings), which you have, so you should be good.

NH3 should usually be at zero (on that rough scale of your tests) - this is something to shoot for. It may rise to 0.25 ppm or between 0 and 0.25 ppm for a short time after a particularly heavy feeding but should come down within hours/half a day.

 

[golum]

thanks for all the help, it might have been to do with not rinsing properly. Well i can check off water parameters to the suspects of killing my adfs...