Bizarre Nitrite test???

[Glenstorm]

Hey All,

Here's one for all you chemistry gurus. . .

I am in the middle of a fishless cycle and my nitrite has peaked and is the process of coming down. The tests just got weird though. . . I am using the Aquarium Pharmacueticals Master Test kit. Directions say to add five drops to 5mL water sample. Initially the sample turns blue, but gradually changes to some hue of purple or magenta. After five minutes it is supposed to be stable.

The weird thing is that my sample seems to to change to a color indicating around 1ppm and then changes back to the inital blue color indicating 0 ppm.

Any ideas what is happening?

 

[NJ Devils Fan]

OMG, the same exact thing happened to me and I asked about it thinking the test was bad. It did that for over a week. When it stays blue, then your water is fine. It gets annoying though because you think like they are at 0, but then you look at it in a few minutes and its light purple and you like. "what the heck just happened". I guess that happens to everyone when they are cycling and using this test kit. Don't worry, it's ok. You'll just have to wait it out until it stays blue.

 

[thom336]

could it be that you have to wait for the test solution to settle before taking the reading from it?

 

[NJ Devils Fan]

you have to wait 5 minutes. when you have no nitrites though, you will know.

 

[thom336]

indeed, as the reactant would have nothing to react with, so you wouldnt get the varying results.

 

[Glenstorm]

Originally posted by NJ Devils Fan
you have to wait 5 minutes. when you have no nitrites though, you will know.

Right, I wait for 5 min and it is the magenta color but at 10 min it is the light blue color. . .

 

[thom336]

check sell by date on your test kit, its a common problem.

 

[valerie]

I had this same problem with my nitrite test when i was doing my fishless cycle(in jan.).It would go dark purple then turn a blueish grey(like the 0ppm reading but different) I wrote the AP people and they said to dilute the test by using 1 tsp tank water to 4 tsp disstiled water. Then take your results and multiply by 5. This will give you the real results.

I was having my problem because the nitrites are too high for the test kits to read.

 

[thom336]

just goes to show that the companies arent just in it for the money, you can always turn to them for help, and that they will happily help you.

 

[Glenstorm]

Originally posted by valerie
I had this same problem with my nitrite test when i was doing my fishless cycle(in jan.).It would go dark purple then turn a blueish grey(like the 0ppm reading but different) I wrote the AP people and they said to dilute the test by using 1 tsp tank water to 4 tsp disstiled water. Then take your results and multiply by 5. This will give you the real results.

I was having my problem because the nitrites are too high for the test kits to read.

Valerie,

Thanks, this sounds like my situation. . . I didn't notice the grey tint but I checked and it had that kind of tint. . . I'll try the dillution.

BTW I never realized 1tsp = 1mL

Dan