James_in_MN
Aquarium Advice FINatic
I think I had a similar issue with my 10g tank that you had with yours. Namely, the nitrItes weren't being consumed as quickly as the ammonia.
My nitrAtes were also very high, mostly because I was fighting the leftovers of two fishless cycles. What happened was, I had to leave on a business trip for nearly two weeks in the middle of my fishless cycle. So, when I resumed my cycle on my return, I already had over 40 ppm nitrAtes in my tank from my first cycle finishing, then stalling.
Once my cycling started back up, my ammonia was disappearing as quickly as I would expect, but my nitrItes were not. They were being consumed, but not nearly as quickly as my ammonia was.
To solve the problem, I did a series of back-to-back water changes, enough to get the nitrAtes down to below 40 ppm, which subsequently brought my nitrItes down to less than 1 ppm. All the while, I was still dosing my tank with ammonia.
Eventually, after getting my nitrAte levels down to manageable, I was able to dose my tank at midnight, let it do its thing while I slept and was at work, and come home to 0 ppm in both ammonia and nitrItes.
It's now my theory that if nitrAte levels are too high, it will drastically slow down your nitrIte consumption. If you get all the numbers under control, I believe that a full cycle, from adding an ammonia dose to getting a reading of 0 ppm ammonia/nitrItes, should be less than 20 hours.
My nitrAtes were also very high, mostly because I was fighting the leftovers of two fishless cycles. What happened was, I had to leave on a business trip for nearly two weeks in the middle of my fishless cycle. So, when I resumed my cycle on my return, I already had over 40 ppm nitrAtes in my tank from my first cycle finishing, then stalling.
Once my cycling started back up, my ammonia was disappearing as quickly as I would expect, but my nitrItes were not. They were being consumed, but not nearly as quickly as my ammonia was.
To solve the problem, I did a series of back-to-back water changes, enough to get the nitrAtes down to below 40 ppm, which subsequently brought my nitrItes down to less than 1 ppm. All the while, I was still dosing my tank with ammonia.
Eventually, after getting my nitrAte levels down to manageable, I was able to dose my tank at midnight, let it do its thing while I slept and was at work, and come home to 0 ppm in both ammonia and nitrItes.
It's now my theory that if nitrAte levels are too high, it will drastically slow down your nitrIte consumption. If you get all the numbers under control, I believe that a full cycle, from adding an ammonia dose to getting a reading of 0 ppm ammonia/nitrItes, should be less than 20 hours.
