Why is my nitrite grey?

[Sharon22]

I’ve tested it three times! It did this to me yesterday so I diluted it with tap water (tap water tested 0 nitrite) and I got crazy bright purple so I did a 50% water change and then the nitrites showed 0ppm. And now it’s testing grey again. This doesn’t make sense to me. If it was off the charts high a 50% water change shouldn’t have knocked it to 0ppm. What is happening? 
 

the photos are about 7min after. The timelapse is 5min. 

[Katherine]

Have you checked the expiration date on the test kit? And is nitrite one of the ones where you're supposed to shake the bottle for a ridiculous amount of time before you use it?

[Tony s]

Yeah, about a full minute before mixing and a minute after. But the results are worth it. Although, the coop strips function really well for ammonia, nitrates and nitrites. Not so much for hard water gh and kh 

[Sharon22]

I shake all the bottles just in case but the instructions don’t specify to shake this one. It’s the nitrate they specify shaking for at least a minute. 
 

Expiration isn’t until 2026  I just bought this kit  

Edited February 9 by Sharon22
Date correction

[Guppysnail]

I have been guilty of not getting the test tube completely clean of previous test solutions and gotten off colors. Also agree check the expiration of the test solution bottle. 

[Sharon22]

I empty the tubes and then run them under warm water, shake them with water, run the under again, shake again, and one last rinse. They they’re still dirty idk how else to clean them lol

[Tlindsey]

On 2/9/2024 at 10:15 AM, Sharon22 said:

I empty the tubes and then run them under warm water, shake them with water, run the under again, shake again, and one last rinse. They they’re still dirty idk how else to clean them lol

I personally rinse mine out with distilled water. Deionized water works as well. 

[Sharon22]

Here is with all three at 5 & 10 minutes. 

[Guppysnail]

The tap one and tank one look fine.  I’m confused as to why you are mixing tap and tank in same vial.  Is there a purpose for that?

[Sharon22]

On 2/9/2024 at 9:56 AM, Guppysnail said:

The tap one and tank one look fine.  I’m confused as to why you are mixing tap and tank in same vial.  Is there a purpose for that?

Because the tank one is actually pretty grey but if I mix the perfectly blue tap with the grey tank I get a greyish purple and that doesn’t make any sense to me