Fishless Cycle

[TwoTankAmin]

OK. We are back to where "when you get .25 ppm or below for ammonia and are clearly below 1 ppm for nitrite, dose it back to 3 ppm and wait 24. Then test."

What looks a little bit odd here is that the either there should be less ammonia or more nitrite. At the end of a cycle one has a balance between the ammonia and nitrite bacteria in that whatever amount of nitrite that the ammonia ones can create, there are sufficient nitrite ones to handle it virtually instantly. However, before that balance is reached, one should be seeing ammonia drop to 0 faster than nitrite can, especially the further through the cycle one is.

Test tonight, more out of curiosity than anything else. But tomorrow morning is the real finish line. We are back to looking to 0/0 within 24 hours of adding 3 ppm of ammonia.

 

[railer20]

Just tested again...
Ammonia seems to be slightly under 1 ppm
Nitrite I would say 1 ppm. Pic is with 2 oz of tank water and 6 oz distilled

 

[TwoTankAmin]

I see the nitrite between .25 and .5. But I am not there, so your view should be more accurate. I really would like to see ammonia under .50 and better yet .25. I would expect nitrite to be down as well so there is not doubt to you that is is under 1.0. I am begining to think there is something in your tank, but not actual ammonia, that is causing a persistent .25 ppm reading that is not real. You may never see a clean 0. So we will be OK with that part of things and look to a 0 nitrite reading that matters.

When you test in the morning, can you test the KH? The bacteria do not require many things, they need ammonia/nitrite, oxygen, inorganic carbon and some other things that should come in with one's tap. We know they are getting the first two but a lot of the third will show up in KH aka carbonate hardness (also temporary hardness). This also acts to buffer a tank's pH which will hold it stable. However, the bacteria can use what contributes to KH to provide the carbon they need. If they deplete the KH enough this can allow the pH to drop.

At the same time the cycle produces nitric acid (nitrate). Acid will work to lower KH. Think of KH like a sponge. It can absorb acid until it cannot absorb any more. At that point, any more acid easily causes the pH to drop rapidly. This is also part of why your pH dropped as it did and why we had to change water. Your bacteria was eating the "sponge" and the cycle was making more and more acid for a shrinking sponge to absorb.

 

[railer20]

There wasn’t much movement this morning. Both tests were slightly lower than what they were last night but nothing close to zero. Do you want me to test the KH in my tank water or the tapwater?

 

[TwoTankAmin]

KH in the tank is what matters the most. However, what is in your tap is where the baseline is. Since the test is so quick and easy, do both?

There is something in your water causing the process to be off. I am not sure if is is something actually slowing the bacterial reproduction rate and/or something affecting the colors of some of the test results. We know things are working because we see drops in ammonia and nitrite levels after adding ammonia. But what the science says should be happening is not.

Here is the problem.

- On Monday you dosed to 3 ppm of ammonia at about 9:30 am your time. You tested the ammonia tank at that time and reported it being 3 ppm and the nitrite at .25 ppm.

- On Tuesday, 22.5 hours later, you tested and reported "Ammonia - between 1 and 2 ppm"- this is a problem because it is not accurate. I do not know if your tank processed 1/3 or 2/3 of the ammonia. That is a big difference. You reported "Nitrites - to me looks to be .5 - 1 ppm." That is a rise in nitrite and it means ammonia is being converted faster than nitrite is being processed. You reported Nitrates 10-20 ppm. This shows nitrite is being processed.

- On Wednesday about 23 hours later you reported "This morning Ammonia - 1 ppm." Now there are only two options here. Either the prior day your ammonia was 2 and has dropped in half to 1 ppm or it was 1 ppm yesterday and no ammonia at all was processed. Therefore, one must assume your 1-2 ppm on Tuesday was most likely 2. But, if you processed 1 ppm in 24 hours the day before, then more than that should be processed in the following 24 hours, But it wasn't..

You reported "Nitrite - 1 ppm" That would have to mean it was either up from .5 or unchanged from 1. Neither of these conditions makes sense. If your ammonia bacteria handled 1 ppm of ammonia in the first day, it produced x Nitrite. And this showed up in the increase in nitrite of between .25 and .75 ppm. Then the next day another 1 ppm of ammonia was reported converted to what should be a similar amount of nitrite. The nitrite bacteria should also have been reproducing over the day such that they should have been able to process more nitrite. But the nitrite did not budge.

I keep coming back to the same conclusion. The numbers should not be what you are reporting. Only two possibilities exist that can cause this. Either you are doing something wrong in testing or there is something throwing off test results, or both. As I stated, cycling is a process. Add ammonia and it doesn't budge for a bit, then it starts to drop and then it does so faster. When the bacteria can convert 3 ppm of ammonia to 0 in 24 hours, you have all of them you need. The same applies to nitrite.

The difference between them is that dosing ammonia instantly creates the amount of ammonia that will normally take a whole day to make in the tank when it is fully stocked. But the nitrite is only created as fast as the ammonia bacteria makes it. So nitrite builds up but at an increasingly slower rate and then it peaks and drops. And the drop here is similar to how ammonia dropped, at an accelerating rate.

This is how the process works. While the exact time and the specific levels can vary from cycle to cycle, the process is the same. What I am seeing in your tank is not even close to following the process. I have asked you to test etc. as I have in such a way as to access what is going on in your tank. And, as you report results, I keep trying to figure out why they are not going as expected.

That leaves us in a strange place. I have to assume one of two things, the first is that your numbers are not accurate but what I am seeing suggests the tank is cycling. The second is there is something wrong and you are not able to get the tank cycled and I cannot say why that is. My gut says the tank is close to being cycled and the problem is the testing, for whatever reason.

So test again this evening. The numbers have to go down. If they do not, I am going to suggest a change in how to proceed from here. First, we will reduce the ammonia dosing by 1/3 and see what happens. If that doesn't change what test results we see, then what I am going to suggest is that you do a big water change and then begin to stock, but not all at once. I am more concerned that nitrite rather than ammonia might be a problem. But that can easily be handled by adding a small amount of salt to the water. And it is easy to spot nitrite issues in a stocked tank, the fish will act as if they need oxygen. Chloride from salt will fix this fast, but I have a hunch it will not be an issue.

Over the years I have occasionally run into such a stubborn situation as this one appears to be. I have learned in such cases to trust that the process is working but that testing is not. The bacteria do not turn off and on back and forth. Either they are there and multiplying as needed or they are not. Since you manage to change ammonia and nitrite readingst on the downside, there has to be bacteria at work. And this means the process is happening. There are too many hints which support this.

 

[railer20]

KH tank - 4 drops - 71.6 ppm
KH tap - 6 drops - 107.4 ppm

 

[railer20]

Tested around 8:00 central time and ammonia was close to .5 and nitrite wasin that 1 ppm range. I did diluted 2 oz / 6 oz so in the AM will do 4 oz / 4 oz and see how that reads.

 

[railer20]

This Morning:
PH - 7.8
Ammonia - real close to .25
Nitrite - pic below looked .5 to me and that is 50/50 mix so 1.0 estimate
Nitrate - approx 40 ppm

 

[TwoTankAmin]

OK- ammonia is doing great. I am still not convinced in tank tests if it will ever hit 0, but time will tell. I had hoped nitrite would be lower but the fact that is is not rising even as more ammonia is being processed is a good thing. You are just about at the point where another dose of ammonia is needed. I am still not happy with the colors in your pictures for nitrite. To my eyes, the color in the tube is not close to anything on the chart. So I have to trust the process to suggest what the level might be. That plus what you see there in person.

What you are waiting for now is for nitrite to drop lower. You want to be able to say unequivocally it is below 1 ppm. There is no longer enough ammonia left in the water to raise nitrite levels or even to keep them constant and that means they have to be going down. The rise in nitrate also tells us nitrite is being processed.

The difference in the KH between your tap and your tank also indicates the cycle is establishing because the bacteria are using carbonates and the acid the cycle produces are using them up some as well. Everything we are now seeing from the testing is telling us things are finally on a good track. The one thing that I still cannot figure out is why your nitrite test colors appear not to match the card colors. Maybe it has something to do with the type of lighting where you are taking the picture?

Please keep an eye on either the pH or the KH in the tank to make sure there is not a significant drop. I do not want to let things stall in the slightest now. 4 dg KH is still OK, but if it hits 2 dg, a 25% water change is needed unless you can get a few ounces of crushed coral to put into a bag in your filter or hanging in the tank in the filter outflow. If you are testing pH, then about 7.2 is where I would take remedial action.

 

[railer20]

I have some crushed coral on the bottom. I will see if I can find a way to hang it over the spray bar outflow.