High Nitrites That Won't Go Down, Think I've Got A Dodgy Test

[Ellieabbott4]

I've had my 20l nano tank set up for 3 weeks now and I used some ceramic media from my mature tank to help with the cycling. In the tank I have 5 endler guppies. I've been testing the water regularly and the ammonia is 0. But every time I test the water the nitrites are off the scale. So I've been doing at least a 50% water change every day. And then testing the nitrite again after a few hours. And the nitrites are still as high as ever. I am using the nutrifen test kit. I have been dosing with seachem prime and even doing the emergency dose for high nitrites and it still isn't going down. Does the seachem prime alter the results on the test kit? I test the water both before and after I do the water change. It seems like the test kit isn't working properly. Surely if I do a 50% water change then the nitrites would half?

 

[b3cca]

Not sure about that kit but maybe it remains the same colour for 5ppm and everything above that. So it could be the nitrites are higher than the kit is actually accurate to and able to read so it simply shows the 5ppm for everything 5 and over
 
Presuming you don't have some crazy high Nitrite tap water then I would try a dilution test and see if you get different readings.
Maybe fill one tube for a normal test and another tube only  quarter the way up with actual tank water and fill the rest with fresh water and see they are  reading different as the diluted one should obviously show  less nitrite than your normal one

 

[tunagirll]

I was just going to say, try testing your tap water or a diluted sample to see if it's working. Is it in date?