Nitrite Test Grey?

[tna2327]

So I have done a fishless cycle before in a 10 gallon tank and it took awhile but it finally finished up. However during that process, I never ran into this issue that I am now running into setting up a new 50 gallon tank. I am about 3 weeks into the cycle and I am already cycling through AM very well however, when I put the test drops into the tube for nitrite, you can see that there is plenty of nitrite as the water turns purple instantly...however over the period of time it asks you to wait, it starts to change into a grey almost clear color. What does this mean? Is there an excessive amount of nitrite? I also started testing for nitrate now that nitrite has been detected and it seems to never go pass the 10-20 ppm mark....any ideas? Just want the tank cycled already so I can move my ever growing pleco into the tank as he is making my 10 gallon tank look like a 2.5 gallon tank lol!

 

[OldMan47]

The funny color that you get after waiting just indicates that the nitrites are way over anything the test can actually measure.

 

[waterdrop]

Agree. Any time you see the reagent drops turn an instant purple you don't even really need to wait for the time period. You already know to record the top number with a plus sign in your log to indicate the nitrite was "off the charts" for the test kit. Often the reagent will form what looks like a shiny pool in the bottom of the test tube. It's usually shiny purple but sometimes can look blue-green to greyish, kind of weird. And yes, if you let it sit then the whole tube will sometimes look gray or a dull version of the weird greenish gray.

Each 1ppm of ammonia is processed in to about 2.7ppm of nitrite by the A-Bacs (the Nitrosomonas spp. autotrophic bacteria.) Even though the two species grow at about the same rate, the N-Bacs are just left with about triple the amount of material to process as the A-Bacs, so their colony must get much bigger than the A-Bac colony.

~~waterdrop~~

 

[anon02]

When my tank was at the "nitrite spike" I found it helped to reduce the ammonia dose to 2ppm, this helps to keep the total nitrogen in the tank down which some people believe benefits both species of bacteria