Is this Nitrite Level concerning? Can I begin adding fish?

[jaymoe17]

Hey all! Been cycling my tank and it’s been all good up until the last 2 days. Nitrites are at 3ppm and nitrates are at 40. Nitrites had been consistently falling from 10ppm until yesterday. My tank processes ammonia in about 24 hours when I dose it up to test which I did for the first time yesterday and it’s almost all gone. It’s weird tho because as nitrites began falling I saw my nitrates fall from 80 to 40. I am using api test strips instead of the liquid for nitrites and nitrates.

I am reading online that as long as I don’t have corals, 3ppm of nitrites are okay for clownfish which I was going to introduce first. What do you all think?

 

[Jay Hemdal]

Hey all! Been cycling my tank and it’s been all good up until the last 2 days. Nitrites are at 3ppm and nitrates are at 40. Nitrites had been consistently falling from 10ppm until yesterday. My tank processes ammonia in about 24 hours when I dose it up to test which I did for the first time yesterday and it’s almost all gone. It’s weird tho because as nitrites began falling I saw my nitrates fall from 80 to 40. I am using api test strips instead of the liquid for nitrites and nitrates.

I am reading online that as long as I don’t have corals, 3ppm of nitrites are okay for clownfish which I was going to introduce first. What do you all think?

Welcome to Reef2Reef!

Nitrite is NOT toxic to marine fish (but is deadly to freshwater fish). I don't have any reports of it being toxic to invertebrates, but maybe?

The only real concern here is that the tank has what I call a "nominally established" biofilter - it is still in the process of developing. While the nitrites are not a fish issue, there may not be a solid population of bacteria yet to handle all of the ammonia produced if you add a group of new animals. Go slow and take your time!

Jay

 

[Randy Holmes-Farley]

The nitrate is likely not that high. Nitrite causes false positives in nitrate.
Good to go with fish!

 

[Garf]

Due to the nitrite falling and nitrite interfering with nitrate tests the apparent nitrate result will also fall, until it reads just nitrate (ish)

 

[jaymoe17]

Welcome to Reef2Reef!

Nitrite is NOT toxic to marine fish (but is deadly to freshwater fish). I don't have any reports of it being toxic to invertebrates, but maybe?

The only real concern here is that the tank has what I call a "nominally established" biofilter - it is still in the process of developing. While the nitrites are not a fish issue, there may not be a solid population of bacteria yet to handle all of the ammonia produced if you add a group of new animals. Go slow and take your time!

Jay

My tank can process ammonia of 2ppm in 24 hrs. Doesn’t this mean bacteria is solid?

 

[Jay Hemdal]

My tank can process ammonia of 2ppm in 24 hrs. Doesn’t this mean bacteria is solid?

2 ppm in 24 hours is great, I'm just saying that issues tend to crop up in new(ish) biological systems, so go slow. Aquariums have what is termed the "microbiome" and that just a term for all of the microbial life in an aquarium that helps support overall stability.

 

[jaymoe17]

2 ppm in 24 hours is great, I'm just saying that issues tend to crop up in new(ish) biological systems, so go slow. Aquariums have what is termed the "microbiome" and that just a term for all of the microbial life in an aquarium that helps support overall stability.

I was going to start with 2 clowns, do you think that’s safe enough?

 

[Jay Hemdal]

I was going to start with 2 clowns, do you think that’s safe enough?

Yes - it is unlikely that a small increase in the bioload from a couple of fish will cause an issue for your biofilter.

That said, adding two clowns to a tank may be an issue if they were not peacefully living together at the store before you bought them ( clownfish, forced together as a pair, may well fight). Ands then, a proper quarantine process will reduce disease issues.

 

[jaymoe17]

Yes - it is unlikely that a small increase in the bioload from a couple of fish will cause an issue for your biofilter.

That said, adding two clowns to a tank may be an issue if they were not peacefully living together at the store before you bought them ( clownfish, forced together as a pair, may well fight). Ands then, a proper quarantine process will reduce disease issues.

So even though my nitrites are at 3ppm, is it okay to get a pair of clowns as my first set?

 

[Jay Hemdal]

So even though my nitrites are at 3ppm, is it okay to get a pair of clowns as my first set?

Personally, I would wait for it to drop, that is a better sign that the tank’s microbiome is a bit more matured.

 

[Garf]

Personally, I would wait for it to drop, that is a better sign that the tank’s microbiome is a bit more matured.

Does the increased likelihood of the water bourne bacteria bloom as below concern you? Nicked it off a freshwater site;

 

[Randy Holmes-Farley]

I would proceed. IMO, ammonia is the concern and what happens after that is not going to cause an issue.

 

[Jay Hemdal]

Does the increased likelihood of the water bourne bacteria bloom as below concern you? Nicked it off a freshwater site;

Since the OP indicated that the tank was consuming 2 ppm ammonia in 24 hours, I just assumed they were dosing with ammonium chloride - the bacteria associated with "bacterial blooms" are the ones that break down surplus food, etc. into ammonia, so not the same group.

I still think that a more mature microbiome is important, a complete population of bacteria and other microfauna makes for a more stable environment - populations of heterotrophic bacteria that deaminate proteins, breakdown chitin, etc.

Not stated, but just as important is the need to have the highest quality fish to add to the tank. All this careful preparation is thrown into the wind if the OP then goes out and buys some junk clownfish from a big box store for their tank.....