Nitrites won't come down?!

Joshua Jordan · Mar 5, 2018

Hi Everyone!

I have been in the hobby for a little over a year now and already have a very successful 32 gallon cube with absolutely pristine water chemistry. (0-Amm, 0-Nitri, Trace- Nitra, 8.2 pH, 420 Cal,) I cycled this tank using the raw shrimp method where I left the shrimp in the tank for a few days, then after a few weeks, everything was kosher.

Now, I have recently started a brand new tank. It is also a cube; a little bit larger at 45 gallons with a 10 gallon sump with about 55 lbs of dry rock and live sand in the display and another 8-10 lbs of each in the refugium as well. I started this tank the exact same way; with the raw shrimp method. Just like the first tank, I had an Ammonia spike and then a Nitrite and Nitrate spike. I have done water testing every single day and once I saw the Nitrates start to drop, I did a 50% water change. However, during this whole time after the Ammonia has been at 0 my Nitrites have not budged! They continue to be at almost the highest possible reading (API test kit). Even after two water changes, nothing....my Nitrie levels are still high and even my Nitrate levels are around 70-80 ppm. It has been 4 weeks, which I know isn't really THAT long but in my first tank, my cycle was much quicker and I am just wondering if I am doing something wrong?

Here is what I have also tried:
I have added some of the mechanical filter pads from my established tank to my new tank.
I have added Seachem Stability

Am I just being impatient, or did I mess up along the way? Please help.

Thanks so much.

CNDReef · Mar 5, 2018

I know if you have nitrites, the nitrate test kit will be high.
I’d be a bit more patient , if you can’t, try taking a sample to a lfs or friend to get a second opinion. Might just be a bad test

Joshua Jordan · Mar 5, 2018

Toomanyfish said:
I know if you have nitrites, the nitrate test kit will be high.
I’d be a bit more patient , if you can’t, try taking a sample to a lfs or friend to get a second opinion. Might just be a bad test

I thought that that may have been the case....but when I run the same test on my established tank I get a 0-Nitrites, 0-Nitrates reading.

CNDReef · Mar 5, 2018

you can try adding bacteria to it
There’s a few out their, I like prodibio from bio digest

Randy Holmes-Farley · Mar 5, 2018

Nitrite is not toxic in a marine system, so generally is not a concern (different from a freshwater tank).

What is the level?

Myka · Mar 6, 2018

What kind of dry rock did you use? It sounds to me like there was significant die off on the rock and adding the shrimp just pushed way too much ammonia into the system.

With 70-80 ppm NO2 you're going to have around 100 ppm NO3. If it was me, I'd be doing a 100% water change to flush some of the NO2 out.

I hope you have the lights turned off during this hard cycle!

Randy Holmes-Farley · Mar 6, 2018

He said 70-80 ppm nitrate, not nitrite

Myka · Mar 7, 2018

Randy Holmes-Farley said:
He said 70-80 ppm nitrate, not nitrite

Ah I see now. Thank you.

So OP, what is the highest the API NO2 kit goes then, what is the NO2 level currently? Personally, I'd still be doing a very large water change to reduce a high NO2 level to help prevent some conversion to NO3. Seeing as there is both NO2 and NO3 in the system now, there is no harm in doing a large water change. Since the OP started with dry rock, the NO3 won't just go away on its own for a long time. Plus, if NO3 ends up being really high you won't be able to add any corals until it comes down to a reasonable level.

chevegan · Mar 11, 2018

There is a great article I wish I could post here that I'm pretty certain Randy authored about 13 years ago a couple years after I started this hobby. I wish I could link it but it's on the devils reef forum. Long story short mortality from nitrite poisoning doesn't even come up until you reach 300ppm+(testing was done on numerous species of fish). Again that's THREE HUNDRED ppm. In fact not until 33ppm did the clownfish being tested (in a separate study) get lethargic and start gasping. SO much incorrect info out there based on unstudied anecdotal evidence. More often than not it's ammonia that's killing fish in instances where people claim it's nitrites. "the more you know!" Thanks Randy! I hope my memory is correct, Randy will let me know I'm sure