Random nitrite spike in aquarium

Hi everyone, so today I noticed one of my fancy goldfish sticking very close to the top of the tank all day so immediately tested the water and am very confused to see a 1ppm nitrite spike. The tank has been cycled for months and going strong, nothing has changed, the only other stock is another fancy goldfish and it’s a 55 gallon tank. I’m gonna do a 50% water change but has anyone got an explanation for what could’ve triggered this ?

 

When was your last water change?

 

Exactly 7 days ago……. I schedule them weekly.

 

How long has the tank been cycled and what does your filter maintenance look like?

 

Do you gravel vac?

 

How long has the tank been cycled and what does your filter maintenance look like?

My tanks been cycled since august last year and I have a fluval FX4 and the tanks internal filter so every 2 months or so I just rinse the sponges out in old tank water.

Do you gravel vac?

Yep I do

 

I think cleaning the filter more often, would help.
How often do you feed them?

 

Did you recently throw out any media?

How much water do you change out every week? And would you please test your tap and tank for PH.

 

I think cleaning the filter more often, would help.
How often do you feed them?

Literally just once a day I feed them, I’m definitely gonna clean out the filter tomo and hope that makes a difference.

Did you recently throw out any media?

How much water do you change out every week? And would you please test your tap and tank for PH.

No,I never threw any media away….i change roughly 30% a week…. I believe my pH is 7.4

 

Will you test both tap and tank? Sometimes a PH crash occurs and this causes the spike.

 

Will you test both tap and tank? Sometimes a PH crash occurs and this causes the spike.

Ignore the results I said earlier ….. tap is 7.8 and tank is 8.2

 

that’s a pretty big difference. Do you have something like crushed coral in the tank?

 

that’s a pretty big difference. Do you have something like crushed coral in the tank?

I do have some Seiryu stone so I’m attributing it to that.

 

Hmm. How long did you have the seiryu sone in there?

 

Very strange, your PH is fine then, no crash.
Did you forget dechlorinator possibly? Honestly I am baffled.

 

Hmm. How long did you have the seiryu sone in there?

I cycled the tank with the stone in there so it’s been ages

Very strange, your PH is fine then, no crash.
Did you forget dechlorinator possibly? Honestly I am baffled.

Seachem prime all the time…. I’m so baffled myself…. It’s wierd coz ammonia and nitrates are absolutely fine but nitrite is strange…. I might test it again later ? Could it have been a false reading ?

 

Could it have been a false reading ?

I have no idea. I'm very confused right now.

 

I recently had what appears to be a false nitrite reading. I'm attributing it to either Prime (I found this possibility mentioned online), or fertilizer.

 

I recently had what appears to be a false nitrite reading. I'm attributing it to either Prime (I found this possibility mentioned online), or fertilizer.

Prime won’t give you a false nitrite reading but maybe fertilizers is an option….

 

I usually don't do this, but I think it's necessary, because there are a lot of wrong infos in this thread and I'm honestly a bit angry about that, as these misinformation could easily make the situation worse.

1. If only ONE fish shows the behaviour described by the OP and a nitrite reading shows up in testing, the likelyhood of it being a measuring error is high.

2. In case of an actual nitrite spike the worst thing one can do is cleaning the filtermedia or the substrate, because there are the beneficial bacteria. So this REMOVES the microfauna that can metabolize the nitrite. Doing a 50% waterchange was the best course of action.

3. A pH of 8.2 to 7.8 is not a big difference. And yes, the Seiryu rocks are very much responsible for this difference.

4. A pH crash is caused by abnormally high (like 100ppm or more) Nitrate values which neutralize the KH and drop the pH down by at least 2 points, if not more. That usually only happens in tanks that haven't been subject to a waterchange in months and don't have plants that consume the nitrates.

5. Fertilizers either contain Ammonium (NH4) which is the harmless version of Ammonia (NH3), or Nitrates (NO3), never Nitrite (NO2). BUT Ammonium can be metabolized by microorganisms just as Ammonia, so this could be a cause for Nitrite readings. But this would also mean this would have happened before.

Could it have been a false reading ?

After reading the thread: Yes. Your fish might just have had a bad day.
Or probably a gill problem. Keep an eye on it. And raise the weekly waterchange percentage to 50%.

Again: In cases of acute Ammonia or Nitrite poisonings ALL fish are affected. So this could not have been the case here.

Also I might want to add: If someone comes with a case like this, PLEASE ask them to fill out the emergency template, that would have answered all questions asked here in one go.