Cycling Question

[Fishcake1]

Hello!

I got a 55 gallon tank over a month ago and I’ve been trying to cycle it using the fishless cycle with Dr. Tim’s ammonia and beneficial bacteria in a bottle. I’ve been following the instructions from Dr. Tim’s website but also referencing the forum here for more information.

I’ve never cycled a tank like this before so I’m not sure if I’m close or already have a cycled tank. At this point in time whenever I add ammonia (per the bottle’s instructions to get an estimated reading close to 2ppm) the tank is able to process it all rather quickly. When I test the water with the API test kit about 24 hours later I have 0 ammonia, .25 nitrite, and between 5-10 nitrate. Then a few hours later the ammonia and nitrite are both 0 and nitrate stays stable between 5-10. It has been like this for over a week now. Everything I’ve read says the tank needs to be able to process all the ammonia and have a reading of 0 ammonia and nitrite within 24 hours to have a completed cycle.

I’m just wondering if this is normal for the tank to be this close to cycling for this long. Does the tank need to process all the ammonia within the 24 hours or is it ok that it processes everything a few hours after. If I were to average what I’ve been seeing it is able to process everything around the 36 hour mark. Is my tank cycled or does it need more time to be able to process everything within 24 hours?

Also if people need it, the temperature in the tank fluctuates between 78-81 F.

 

[powerdyne6]

I did my 15 gallon using Dr. Tims ammonia and it took probably 8 or 9 weeks.

You will know when it is ready.

I put in enough ammonia to see a reading of about 4 or 5 ppm and by the next day it was gone.

I knew it was ready at that point.

Be patient you are close

 

[TwoTankAmin]

If you did it right and your water parameters are in the proper range, your tank should have been fully cycled in about 2 weeks. And yes ammonia and nitrite both need to be 0 withn 24 hours to add fish.

I used to use Dr. T's Ammonium Chloride but it was more economical to use the Fritz dry form and make my own solution. Last time 15 filters for 8 tanks holding 220 gals and it went pretty fast. To save some money I normally add about 1/2 the amount of recommended Dr. T's bacteria and then I rinse out a number of my established filters in the tank as well.
https://www.fishforums.net/threads/...o-go-into-8-summer-tanks.481266/#post-4178063

A cycled tank will process 3 ppm of ammonia to nitrate in 24 hours or less. It is important to understand that, an established cycled tank with a full load of fish will never create 3 ppm the way it is created when we add it for a fishless cycle- all at once. The ammonia will be created 24/7 in small amounts that vary over a 24 hour day. So even though that may add up to even more than 3 ppm, it only needs to be cleared as fast as it is created. We cannot create this gradual steady dosing manually. So we dump in the 3 ppm all at once. If the tank can convert the entire amount to nitrate in 24 hours or less, that requires sufficient bacteria to consume what a fully stocked tank should create over afull day.

Next, the bacteria in the bottle is alive but basically asleep. Ammonia etc. wakes it up and it goes to work. There are also sufficient number of bacteria that can handle the amount of nitrite that will be produced by what ever ammonia those bacteria can convert to nitrite. The bacteria in the bottle are essentially "cycled." The only issues are the awakened enough and in sufficient numbers to handle your specific tank. This may take a few days (7-14) before you can stock fully and safely.

I see a few potential explanations for what you are seeing but would need more info to get a better idea. pH of the water, KH of the water. Also, I tend to look at the lab grade tests to find out what can cause false or inaccurate readings. Looking at the $208 Hach nitrite.nitrate kit it says:

Nitrite
• Undissolved reagent does not have an effect on test accuracy.
• Strong oxidizing and reducing substances interfere with the test. Cupric and ferrous ions cause
low results.

from https://www.hach.com/asset-get.download.jsa?id=52007261903
Dechlor is a reducing agent. Cupric means copper and ferrous means iron.

So, your persistent very low .25 ppm of nitrite may very well be a false reading due to something else. This would be be the most probable issue. The nitrite bacteria are slow to double, but they can still easily do it twice in one day.

Finally, the result of a known ammonia addition can only produce a specific maximum calcuable amount of nitrite and then nitrate. In the world of science, which uses the Nitrogen Scale to measure it all, they are only interested in the N part of these things so, 1 ppm of total ammonia (NH3 + NH4) = 1 ppm of nitrite (NO2) = 1 ppm of nitrate (NO3). However, most hobby test kits measure on the Total Ion scale which means they also coubt the Hs and Os. Here 1 ppm of Ammonia can produce about 2.6 ppm of nitrite and then about 3.5 ppm of nitrate. When you add 2 ppm of Dr. Tim's ammonium chloride the 2 ppm of ammonia it should create will be about 2.6 ppm on and API type test kit.

The above math means every time you add that 2 ppm of Dr. Tim's and are using a API type kit, you can be creating over 6 ppm of nitrite. To get a constant .25 ppm of nitrite as you appear to is almost impossible. If the bacteria have all they need and they are able to handle all the 6+ ppm of nitrite but .25 ppm, in 24 hours they should be able to handle double that easily. Yet they appear not to do this.

I doubt you are stalled. Pretty much a lot of what the bacteria converting nitrite to nitrate need, the ammonia ones need as well. If one stalls so does the other. But this isn't happening. However your nitrate should be high except for those tests being flakey. So the things I am wondering is if you are you doing any water changes, what dechlor you use and how often are you using it and at what dosing level? Some of these can cause false readings for after 24 -48 hours before they stop working, Example:

How long does Prime® stay bound to the ammonia, nitrite, and nitrates?

A: Prime® will bind up those compounds for up to 48 hours. If they are still present after that time frame, they are released back into the water, unless Prime® is re-dosed accordingly. Also, if your ammonia or nitrite levels are increasing within a 24-hour period, Prime® can be re-dosed every 48 hours.

from FAQ https://www.seachem.com/prime.php

Up to also implies it may be less

There is also one last possibility involved here. You say you are following Dr. Tim's. If so you should not be referencing anything else unless it is curiosity and you are ignoring what it says. Mixing methods rarely works well. I wrote the fishless article here and it is based on Dr. Tim's method when his bacteria is not used. However, it allows for a build up of nitrite to a level 3 times the max. level an API type kit can measure before that can stall a cycle. So it means one has to do diluted testing to discover the problem if the cycle does stall. The method here used the same total dosing of ammonia during the cycle but it changes when and how much ammonia is added. This makes it impossible, when followed to the letter, to create enough nitrite to stall things. So no diluted testing will be needed.

Can you provide all the info I assked about please and this may make things more clear as to what is going on in your tank.

 

[Fishcake1]

Hello @TwoTankAmin,

Thank you for your knowledgeable insight!

To answer all your questions here is all the info you requested:

KH : about 4 dKH or 80 ppm

Ph: stays around 7.4

Water Changes: I’ve only done two water changes since I’ve had the tank set up and it was more because I was having some plants melt a lot and they were mucking up the water. I’ve only ever done water changes when there was no ammonia or nitrite in the tank and the nitrate was still around 10 ppm.

Dechlor: I’ve only added it when I did the water changes and when I initially put the water into the tank the first time. I use API stress guard and I use the recommended dosage (half a cap for every 10 gallons so I added 2.75 capfuls)

Instructions: I followed Dr Tim’s instructions completely. I browsed the forum here but did not follow the directions just read it cause I was curious.

I do have a heavily planted tank which I know can affect the cycling process as well.

Hopefully I’ve answered all the questions you had and provided further insight into my situation. Thanks!

 

[Fishcake1]

@TwoTankAmin so are you saying that my .25 nitrite reading could be false considering I’m not doing anything else suggested like adding dechlor often or doing water changes often?

 

[TwoTankAmin]

Yes- that may be the case and I have one more Q. Are you adding ferts for the plants?

One way to make sense out of a persistant low level reading that never changes is to ask yourself this. If you wanted to create this situation in a tank, could you do it? Ny answer is no. There us no way in your tank that you could make a persitant .25 ppm reading of nitrite such that if you tested as you have been doing, you sowuld be able to get a .25 ppm reading every time.

You would need a pile of pricey equipment to replicate what you are seeing.

Moreover, the bacteria will reproduce if there is more ammonia or nitrite than they need to thrive. So you add ammonia and it goes away as expected. We also know that where most of it is going is to become nitrite. Now if there are not eough nitrite bacteria to handle the amount of nitrite orest, they will reproduce. So very quickly the tank will handle and excess .25 ppm. To get another .25 ppm nitrite reading you would have to add move ammonia than the previous time.

And you are right that the plants matter. The plants want ammonium and they can use it way faster than the bacteria can use ammonia. However, unlike the bacteria, plants to not make nitrite or nitrate. So you actually need few nitrite bateria than it would reayuired if only bacteria were consuming ammonia. So you should actually be seeing less nitrite than expected not more.

The only explanation for your .25 ppm reading is that it isn't real. Something else is causing you to get a false reading. Kniwin what is nit as easy to determine as figuring out the reading cannot be from nitrite. Also, I am surprised you are getting much of a nitrate reading will a lot of plants. They will use nitrate when they are not getting enough ammonia. So many well planted tanks may never see nitrate.

I would consider your tank cycled and do a big water change and add fish.

Finally, live plants arrive with some of the nirtifying bacteria one them. It is virtually impossible for there not to be some bacteria even in the most heavilty planted tank. As long as there is some ammonia present, there will be bacteria. On the other hand it is possible to have a tank be completely cycled with only bacteria and not a single live plant.

 

[Fishcake1]

Yes- that may be the case and I have one more Q. Are you adding ferts for the plants?

One way to make sense out of a persistant low level reading that never changes is to ask yourself this. If you wanted to create this situation in a tank, could you do it? Ny answer is no. There us no way in your tank that you could make a persitant .25 ppm reading of nitrite such that if you tested as you have been doing, you sowuld be able to get a .25 ppm reading every time.

You would need a pile of pricey equipment to replicate what you are seeing.

Moreover, the bacteria will reproduce if there is more ammonia or nitrite than they need to thrive. So you add ammonia and it goes away as expected. We also know that where most of it is going is to become nitrite. Now if there are not eough nitrite bacteria to handle the amount of nitrite orest, they will reproduce. So very quickly the tank will handle and excess .25 ppm. To get another .25 ppm nitrite reading you would have to add move ammonia than the previous time.

And you are right that the plants matter. The plants want ammonium and they can use it way faster than the bacteria can use ammonia. However, unlike the bacteria, plants to not make nitrite or nitrate. So you actually need few nitrite bateria than it would reayuired if only bacteria were consuming ammonia. So you should actually be seeing less nitrite than expected not more.

The only explanation for your .25 ppm reading is that it isn't real. Something else is causing you to get a false reading. Kniwin what is nit as easy to determine as figuring out the reading cannot be from nitrite. Also, I am surprised you are getting much of a nitrate reading will a lot of plants. They will use nitrate when they are not getting enough ammonia. So many well planted tanks may never see nitrate.

I would consider your tank cycled and do a big water change and add fish.

Finally, live plants arrive with some of the nirtifying bacteria one them. It is virtually impossible for there not to be some bacteria even in the most heavilty planted tank. As long as there is some ammonia present, there will be bacteria. On the other hand it is possible to have a tank be completely cycled with only bacteria and not a single live plant.

@TwoTankAmin Thanks for this information! I was dosing fertilizer at the beginning before I got the ammonia and bacteria in the mail just to feed the plants that were in there. After I started the cycling process I stopped to make sure I wasn’t messing or confusing the cycle. Since the cycle is now complete and I won’t be adding any more ammonia I’ll start dosing again.

Thanks for all your help!

 

[TwoTankAmin]

The plants will use ammonia as NH4 in which form most ammonia in takes exists. Given enough plants which also host some bacteria, one can do w/o cycling if one stocks over time as opposed to all at once.