eco23
Aquarium Advice Addict
To put this simply...you do NOT need to do water changes every time your nitrItes are high during a fishless cycle.
For some reason this advice is being passed around the site, but it is simply not true.
High nitrItes are an expected phase of cycling a tank. This is one of the reasons people choose to do fishless cycles, so you don't have to stress about your fish or constantly changing water every time it spikes.
There is some debate whether sky high nitrItes actually become toxic to the bacteria, but in my opinion it would take ridiculously high levels for that to even become plausible. My belief is that stalls and pH crashes are not normally caused by the nitrIte levels themselves...they are caused by the nitrifying bacteria using up the nutrients and buffers in the water during the process of PRODUCING the nitrItes and nitrAtes. A pwc or two at the height of your cycle will restore those things and also reduce the no2 in the process.
Pwc's wont hurt. I personally recommend doing 1 or 2 during the process to restore the nutrients and alkalinity that will prevent the crashes and stalls. If you'd like you can even do a massive one (90%) to really get the number down. But again, not every couple days like is recently being advised.
Now, if you're past due for completing your cycle and you want to try a little trick, you can get the no2 down to .5-1 with a large pwc, and then only dose the ammonia to ~1ppm for 3-4 days. That will slow the nitrIte production and potentially give the no2 > no3 bacteria a chance to catch up. This normally isn't necessary, but if you feel things aren't finishing when they should...it won't hurt to try.
If you enjoy doing water changes every day or two...there really isn't a need to be doing a fishless cycle, you might as well have fish in the aquarium because the constant pwc's would be keeping the toxins down anyway. We WANT toxins in the tank during a fishless cycle.
Thanks
For some reason this advice is being passed around the site, but it is simply not true.
High nitrItes are an expected phase of cycling a tank. This is one of the reasons people choose to do fishless cycles, so you don't have to stress about your fish or constantly changing water every time it spikes.
There is some debate whether sky high nitrItes actually become toxic to the bacteria, but in my opinion it would take ridiculously high levels for that to even become plausible. My belief is that stalls and pH crashes are not normally caused by the nitrIte levels themselves...they are caused by the nitrifying bacteria using up the nutrients and buffers in the water during the process of PRODUCING the nitrItes and nitrAtes. A pwc or two at the height of your cycle will restore those things and also reduce the no2 in the process.
Pwc's wont hurt. I personally recommend doing 1 or 2 during the process to restore the nutrients and alkalinity that will prevent the crashes and stalls. If you'd like you can even do a massive one (90%) to really get the number down. But again, not every couple days like is recently being advised.
Now, if you're past due for completing your cycle and you want to try a little trick, you can get the no2 down to .5-1 with a large pwc, and then only dose the ammonia to ~1ppm for 3-4 days. That will slow the nitrIte production and potentially give the no2 > no3 bacteria a chance to catch up. This normally isn't necessary, but if you feel things aren't finishing when they should...it won't hurt to try.
If you enjoy doing water changes every day or two...there really isn't a need to be doing a fishless cycle, you might as well have fish in the aquarium because the constant pwc's would be keeping the toxins down anyway. We WANT toxins in the tank during a fishless cycle.
Thanks
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