Messed up cycle..

[twentyleagues]

Jeez, are you brandon with a different acc? (where is brandon btw, did I miss some major drama while I was away in the last couple of years).

Cycling is finished when nitrites are converting to nitrates. Most of fishkeepers and every single bottled bacteria manufacturers thinks this way, thats why their product contains bacteria to convert nitrites as well.

There are many studies out there about nitrite toxicity, its definitely not beneficial for fish in higher concentrations, if these are too high level for some, there is dr tims article for beginners, mentions nitrites a few times: https://www.drtimsaquatics.com/resources/fishless-cycling/

Nitrites are not toxic to saltwater fish at the levels we could/would achieve, it would take nitrites in the 100s of ppm to be toxic. Having had freshwater aquariums all my life and my last saltwater stint from '99-2010 coming back in '21ish this was a hard thing for me to grasp also. I am still decided on the cycle needs to be complete before I add stuff but its no longer about if nitrite will harm my inhabitants its more about seeing the cycle established. I am willing to wait I am not in a hurry. The base fact here that I think you may be getting hung up on is the same with people using API test kits, that .25 is probably an inaccuracy in the test itself and even if it is .25 or less that is also not toxic. I guess op could do a nitrite test just to see if there is nitrite present even though it would not matter. Time the tank has been running and the fact they used ammonia and bacteria to start the tank means its cycled at least to a safe enough point to add fish. Adding fish now will increase the biome, gut bacteria from the fish will help the process.

 

[dinosaur_1552]

Time the tank has been running and the fact they used ammonia and bacteria to start the tank means its cycled at least to a safe enough point to add fish.

That's unfortunately not true, there could be chemicals/toxins/chlorine etc in the water which makes it impossible to cycle. If I drop bacteria and ammonia in a tub of sulfuric acid it won't be cycled and I cant add fish to it later.

Thats why its handy to have test kits and follow the cycle to see if the first life you introduced, the bacteria, is surviving, so conditions are suitable for basic forms of life.

this was a hard thing for me to grasp also

There is nothing hard to grasp in this. There are plenty of studies out there with the exact lethality figures of ammonia and nitrite on saltwater juvenile aquarium fish, like clownfish, both ppm vlaues are much higher than ppl normally think.

With careful feeding and with a bigger tank, lets say 150L upwards, you could chuck in two juvenile clowns without any bacteria and they would not even blink in the 3-4 weeks while ammonia starts to get reduced.

But just because you could, that doesn't mean you should, and there are multiple reasons for that.

First is that it might not be nice for fish to swim in ammonia or 25 nitrites even though it might not kill it. You might want to prepare their home as best as you can, you want to be sure cycle is done and works for the inhabitants - as a responsible person.

Second is that while many could confidently cycle as above, without anything, newcomers mostly don't know what they are doing and and its a good idea to learn what exactly happens in the tank. A nice way to learn the biological filter it is to follow ammonia->nitrite->nitrate through your test kits.

If someone doesnt know where his cycle is, like OP, and he has all the test kits, the answer is be patient for one more day, test it to get a 100% confirmation where your cycle is. He is likely cycled anyway, why not confirm if he is unsure, then he can move forward. Do one thing at a time.

 

[twentyleagues]

Ok lets break this down since it seems you are missing the point of my post.

You: That's unfortunately not true, there could be chemicals/toxins/chlorine etc in the water which makes it impossible to cycle. If I drop bacteria and ammonia in a tub of sulfuric acid it won't be cycled and I cant add fish to it later.
Me: We are going on the assumption this is not the case since they are/were testing and tests showed ammonia added going down and nitrates rising months ago. Also why would you put fish in sulfuric acid?

You: There is nothing hard to grasp in this. There are plenty of studies out there with the exact lethality figures of ammonia and nitrite on saltwater juvenile aquarium fish, like clownfish, both ppm values are much higher than ppl normally think.
Me: You contradict yourself. It is or isnt lethal at our achievable numbers. You said the numbers are much higher than what people think and it is much higher so high in fact that we probably can not achieve it in the time frame that the bacteria would start handling it. It would take an extraordinary amount of fish or ammonia to produce the amount of nitrite for this to happen in a standard reef tank. So a non-issue. Freshwater is different and pretty much any amount of testable nitrite is dangerous if not deadly.

You: But just because you could, that doesn't mean you should, and there are multiple reasons for that.
Me: As I stated I like to see that a complete cycle exists. Even though I said that and stick to it I also see the benefit of increasing biodiversity once ammonia is being converted by adding a few fish. The nitrite is not toxic or detrimental at most levels we can achieve and there fore can be ignored and in fact adding fish and feeding them can help the nitrites cycle as you are adding phosphate that may not be added normally and the bacteria that use nitrites also need phosphates. Also added bacteria from the fish will help the biodiversity.

You: First is that it might not be nice for fish to swim in ammonia or 25 nitrites even though it might not kill it. You might want to prepare their home as best as you can, you want to be sure cycle is done and works for the inhabitants - as a responsible person.
Many people: Nitrite is a non issue in our reef tanks.

You: Second is that while many could confidently cycle as above, without anything, newcomers mostly don't know what they are doing and and its a good idea to learn what exactly happens in the tank. A nice way to learn the biological filter it is to follow ammonia->nitrite->nitrate through your test kits.
Me: actually I agree.

You: If someone doesnt know where his cycle is, like OP, and he has all the test kits, the answer is be patient for one more day, test it to get a 100% confirmation where your cycle is. He is likely cycled anyway, why not confirm if he is unsure, then he can move forward. Do one thing at a time.
Me/us: I think most of the ops issue is the ammonia test reading .25 which is likely a fact of the tests inaccuracy at that low level. With the amount of time, bacteria added and ammonia added it is cycled.

 

[Reefering1]

 

[BeanAnimal]

Cycling is finished when nitrites are converting to nitrates.

“cycling is never finished” but if we are being pedantic, then it would be finished when nitrates are converted back nitrogen gas and oxygen.

The only part that really matters in the context of “cycling” here is that ammonia is being processed to a safe enough level for marine fish and invertebrates.

thats why their product contains bacteria to convert nitrites as well.

I suggest looking at bottled bacteria assays, most contain heterotrophs, not nitrifiers.

There are many studies out there about nitrite toxicity, its definitely not beneficial for fish in higher concentrations, if these are too high level for some, there is dr tims article for beginners, mentions nitrites a few times: https://www.drtimsaquatics.com/resources/fishless-cycling/

Not beneficial is not harmful.

I suggest that you read those studies that you mention. You will find that they show nitrite is not harmful to marine fish due to the presence of chloride. The dangerous levels of nitrite start in the hundreds of ppm (300-500) depending in the species.

The article is a sales pitch. Nitrite is listed as being highly toxic in freshwater, but toxic levels in saltwater are carefully avoided.

You mention "studies". Yes, there are numerous scientific studies done on nitrite toxicity in marine systems and they contradict your position:

Kroupová et al. (2005, Vet Med 50(11): 461-471) — “The effect of chloride concentration is decisive; in seawater nitrite toxicity is minimal.”

Lewis & Morris (1986, Chemosphere 13 (9–10): 1397-1404)
“Nitrite toxicity is greatly reduced in seawater because chloride competes with nitrite for uptake across the gill.”

Meade (1989, Aquaculture 81: 63-72) — “Marine species tolerated nitrite-N concentrations exceeding 300 mg/L without mortality.”

Lewis & Weis (1978, Mar Biol 47: 117-122) — “No mortality or sublethal effects in Fundulus heteroclitus up to 500 mg/L NO₂-N.”

There are dozens more. So, regardless of what bottled bacteria vendors put in their sales pitches and what reef keepers tell each other, nitrite is not toxic to fish in our systems.

 

[dinosaur_1552]

We are going on the assumption this is not the case

Thats exactly the issue with your approach.

You can't assume that everything you don't know will have an outcome favourable to you and hope fish will live.

If it would be that simple I could assume lottery numbers every week

Thats the very reason we have test kits, cause asssumptions didn't work, we don't want to play lottery with the life of the fish.

If you don't know something, look for confirmation and make opinion based on the facts, not assumptions.

A very basic test before you put those first fish into the water is to see if bacteria can survive and grow at all, don't just assume water is good.

If you don't know where you are in the cycle - as op stated -, you test it, as you have all the tools and it costs nothing and go on from there.

I try not to react to the rest, everyone made their points already

 

[Fish Fan]

This is all anyone needs to know about nitrite toxicity. It is very much a non-issue in marine tanks, and many here at R2R don't bother testing for it at all:
https://www.reef2reef.com/posts/4805029/
@ZachariahBeanzz did you get a new fish?

 

[twentyleagues]

Thats exactly the issue with your approach.

You can't assume that everything you don't know will have an outcome favourable to you and hope fish will live.

If it would be that simple I could assume lottery numbers every week

Thats the very reason we have test kits, cause asssumptions didn't work, we don't want to play lottery with the life of the fish.

If you don't know something, look for confirmation and make opinion based on the facts, not assumptions.

A very basic test before you put those first fish into the water is to see if bacteria can survive and grow at all, don't just assume water is good.

If you don't know where you are in the cycle - as op stated -, you test it, as you have all the tools and it costs nothing and go on from there.

I try not to react to the rest, everyone made their points already

I assumed because tests were done and ammonia did go down so environment is favorable. You are grasping at straws to validate some idea that is not valid. Op tested for ammonia and nitrates and got answers. Yes they did test .25 ammonia but that is likely margin of error for the test. I would suggest leaving it there and do more research on these subjects.

 

[dinosaur_1552]

This is all anyone needs to know about nitrite toxicity. It is very much a non-issue in marine tanks, and many here at R2R don't bother testing for it at all:
https://www.reef2reef.com/posts/4805029/
@ZachariahBeanzz did you get a new fish?

I did read this article years ago when I was interested in this topic (I was pushing the limits of hospital tanks sizes due to lack of space) and I actually found the original sources he refers to and read those originals as well.

One of the issues with this article is that the ONLY small ornamental species listed are clowns, rest is atlantic cod etc, which are massive fish and in a totally different ballpark in terms of susceptibility to toxic materials. Clown is one of the hardiest ornamental fish we have, plenty others are likely much more sensitive and will likely have much lower tolerances than clowns.

But even with the hardy clowns let's see what the article states "two of five fish died after a few days at 330 ppm, giving an LC50 not appreciably different from the other species listed in Table 1. At 33 ppm (the next dose down from 330 ppm), the fish were lethargic and breathing with difficulty".

Breathing difficulity at 33ppm? Would you say then that half of that, 16ppm is safe? I wouldn't.

And 16ppm nitrite is coming from only 6ppm total ammonia which you can easily introduce in a cycle if you dose to 2ppm a few times.

And this is one of the hardiest ornamental fish we know, not the sensitive ones!

I actually discussed this with Randy at that time and my main takeway was that while nitrite is around 30-50% less toxic than the ammonia it got converted from (depending on ph as more ph = more free ammonia), it can be still a factor and likely not a pleasent experience for fish - if we ASSUME that anything close to breathing difficulties is not pleasant.

 

[Fish Fan]

I did read this article years ago when I was interested in this topic (I was pushing the limits of hospital tanks sizes due to lack of space) and I actually found the original sources he refers to and read those originals as well.

One of the issues with this article is that the ONLY small ornamental species listed are clowns, rest is atlantic cod etc, which are massive fish and in a totally different ballpark in terms of susceptibility to toxic materials. Clown is one of the hardiest ornamental fish we have, plenty others are likely much more sensitive and will likely have much lower tolerances than clowns.

But even with the hardy clowns let's see what the article states "two of five fish died after a few days at 330 ppm, giving an LC50 not appreciably different from the other species listed in Table 1. At 33 ppm (the next dose down from 330 ppm), the fish were lethargic and breathing with difficulty".

Breathing difficulity at 33ppm? Would you say then that half of that, 16ppm is safe? I wouldn't.

And 16ppm nitrite is coming from only 6ppm total ammonia which you can easily introduce in a cycle if you dose to 2ppm a few times.

And this is one of the hardiest ornamental fish we know, not the sensitive ones!

I actually discussed this with Randy at that time and my main takeway was that while nitrite is around 30-50% less toxic than the ammonia it got converted from (depending on ph as more ph = more free ammonia), it can be still a factor and likely not a pleasent experience for fish - if we ASSUME that anything close to breathing difficulties is not pleasant.

You're contradicting the advice of some of R2R's most well respected members in this thread (as well as RHF), and arguing needlessly over the OP's thread. I'd suggest that you start your own thread on this topic if you'd like to discuss it further, out of respect for the OP or for others that may find this thread in the future