New cycling problem

[trcon17]

Probably dumb on my part but I bought another canister filter (Sun Sun 704b) to go with my existing Cascade 700 canister and my Penguin 200 HOB filters. I was in the middle of cycling the new 75 gallon tank when I added the large Sun Sun canister filter. I wanted a lot of filtration because my goal is to stock it with a lot of MBuna cichlids. I was about three weeks into the cycle and was seeing Nitrites rise as well as Nitrates starting to show readings all the while keeping my ammonia at around 3 to 4 ppm. After I added the new filter and waited a couple of days my ammonia was at 1 to 2 ppm but Nitrites and Nitrates dropped back down to 0 ppm. My PH has remained at 7.8 to 8.0 all along and is currently at 7.8. Does this seem right? Why would the Nitrites and Nitrates disappear with the addition of more filtration and no water changes?

 

[ZxC]

Probably dumb on my part but I bought another canister filter (Sun Sun 704b) to go with my existing Cascade 700 canister and my Penguin 200 HOB filters. I was in the middle of cycling the new 75 gallon tank when I added the large Sun Sun canister filter. I wanted a lot of filtration because my goal is to stock it with a lot of MBuna cichlids. I was about three weeks into the cycle and was seeing Nitrites rise as well as Nitrates starting to show readings all the while keeping my ammonia at around 3 to 4 ppm. After I added the new filter and waited a couple of days my ammonia was at 1 to 2 ppm but Nitrites and Nitrates dropped back down to 0 ppm. My PH has remained at 7.8 to 8.0 all along and is currently at 7.8. Does this seem right? Why would the Nitrites and Nitrates disappear with the addition of more filtration and no water changes?

You did the test wrong, there isn't any other place for the nitrates to go, unless you somehow managed to build up an anaerobic bacteria population (next to impossible in a few days).

 

[libertybelle]

You did the test wrong, there isn't any other place for the nitrates to go, unless you somehow managed to build up an anaerobic bacteria population (next to impossible in a few days).

could be that. Nitrate tests are notorious for being a pain. If you didn't shake the reagent bottle 2 really well it won't work properly.

Could also be a real drop if there are plants in the tank?

 

[trcon17]

I have noticed when I apply a dose of ammonia it reduces to a lower level within 24 hours however there are zero nitrites and small amounts of nitrates. I am only four weeks into the cycle but shouldn't I be seeing the nitrites spike high after adding ammonia? And if I am not mistaken the nitrites and nitrates will then spike high at the same time eventually. Is this correct?

 

[drjallen3]

I have noticed when I apply a dose of ammonia it reduces to a lower level within 24 hours however there are zero nitrites and small amounts of nitrates. I am only four weeks into the cycle but shouldn't I be seeing the nitrites spike high after adding ammonia? And if I am not mistaken the nitrites and nitrates will then spike high at the same time eventually. Is this correct?

If you're showing nitrates at all, the Nitrobacter may actually be populated enough to get rid of the nitrites quickly, but that seems extremely unlikely. I'm going to go along with the other post that you may have made a mistake in your nitrite testing. If you show any nitrates but 0 nitrites, repeat the nitrite test. It's not impossible that your nitrite reagents are faulty. You may need to get another nitrite testing kit.

 

[trcon17]

Well an update on my problem... I did a large (95%) water change and wallah. Tank cycled. Kind of weird. A large water change and testing showed the tank was fully cycled already.

 

[ZxC]

What were the reading before / after the water change?