What to do when your Nitrite wont fall during Fishless Cycle

oneilwiz

New member
How can you reduce the Nitrite measuring over 5PPM during Fishless Cycling?

High Nitrite for 13+ days while Ammonia drops to 0ppm. I have done a 40-gallon water change but still high purple reading. I am lost not sure what to do.

Size tank: 120G
Temp: 80
Salinity: 35ppt
Ammonia: Dr Tims
Bacteria: Dr Tims one and Only
Rocks: Carib sea Life rock (dry)
Sand: Caribsea Dry Sand
Water: RO
Cycle Started: Sept 16,2020
Test Kit: API Nitrite and Ammonia

I have seen a few post that says to wait it out, don't add any more ammonia. I goal for this thread is to provide a 1 stop source for new reefers when they face the same challenge of high nitrite for weeks.
 
Last edited:
If there's nothing in the tank I wouldn't worry about it right now. Are you reading nitrates? You could also take it into an lfs and see what they get. Could be a faulty test
 
Frankly in multiple decades I've never tested nitrite/trate in a cycling tank. I'll deal with whatever it is after I start with snails.
 
Starting with dry rock, you should get there in about 8 weeks. You might try also ghostfeeding the tank, ie, micro pinch of fish food delivered until it turns toxic with ammonia, keep at it until it clears to 0--- Bacteria do need to eat to reprodce. Maintain your salinity carefully.
 
Thank you all for your help, here is a quick update.

I did a major water change ( 40G), while Nitrite was still high. I realized I had a bottle of Brightwell MicroBacter 7 on hand. So since my Ammonia has been 0 for the past two weeks-plus, I started to dose Bacter 7 daily. After two days the Nitrite fell to 0.

Now, of course, this product does bind nitrite, etc so I wouldn't say is the best approach but it works. I have had my clownfish in the tank for the past few days no issues while I am still monitoring water parameters. I do tend to slowly add a fish or to every two weeks, or so since my old tank of course is leaking. I decided to add the Bactor 7 for several reasons after reading its content and benefits etc.
 
13 days into a cycle that's likely to take two months seems to be right on schedule, in my opinion. Of course Nitrites are high. They're supposed to be at this point. You've got to keep adding an ammonia source to power the cycle, and get the good bacteria up to speed and capacity. Adding fish at this point is risky, as conditions will fluctuate widely. This will likely lead you to performing more water changes to keep those fish alive, slowing the cycling process down. Also, binding up Nitrite at this point slows down the cycling process. It's the 'food' that the good bacteria need to get established. Unfortunately, you have likely made the cycle take longer.

The process of cycling can be confusing and tricky. It is a natural process that cannot be 'outsmarted'. You just have to wait it out.

Your fishless cycle was a good plan. Stick to it. No need to test until you hit 2 months.
 
My Aplogies everyone, I saw a few mistakes I made in this thread;
Cycle Started: August 16,2020 NOT Sept

Also where I mentioned "Now, of course, this product does bind nitrite" bind is not the right word to use here as well as please not am not a chemist/ marine biologist.

In summary my tank has been up and running for 31 Days. Thank you all for your assistance.
 
In short - be patient. If it simply won't go down, consider that rock or sand may be leaching nastiness. That tends to be more phosphates, but any nutrient can leach.
 
Can't say how long it's been since I've tested nitrites. Add some sand from an established reef or some pieces of maricultured live rock.
 
Back
Top