Simplified Fishless Cycling Instructions

xxBarneyxx

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So the main sticky for Fishless cycling is great but it suffers a little from information overload and that makes it hard for some to follow the instructions. I thought I would have a go at a "condensed" version. This is in no way meant to replace the original instructions but just act as a quick reference in addition to them.

Please do point out any issues or mistakes I may have made. Putting this together while waiting on installs to finish so had to jump in and out of it a few times.

Quick Reference - Fishless Cycle
First you should fully read the link below. This explains in detail why we need to do a fishless cycle and how. These instructions are meant as a quick reference and supplement to the original thread.

Original Fishless Cycle Thread

Day 1 – Dose Ammonia to 3ppm. Use https://fishforums.net/aquarium-calculator.htm to work out how much Ammonia to use. After 30 minutes, test the tank water for Ammonia to make sure it is around the 3ppm range. Make a note of how much Ammonia you used. Now wait 2 more days before starting "Stage 1 - Firsts Tests".

Stage 1 - First tests Test Ammonia and Nitrite every 3 days.
Is ammonia under 0.75 ppm and Nitrite over 2ppm?
If No repeat this step in 3 days.
If Yes Add the same amount of Ammonia as you added on Day 1 and go to “Stage 2 – Snack Dose”.

Stage 2 - Testing for “Snack Dose”,
Test Ammonia every 2 days – You are now looking for Ammonia to go to zero. When Ammonia has been zero for 2 tests in a row (4 days with 2 tests) you need to add a “snack dose”. This is 1/3rd of your original dose. You only need to do this “snack dose” now, once you have done it go on to “Stage 3 - Daily Testing”.

Stage 3 - Daily Testing – Test Ammonia and Nitrite.
Is Ammonia Under 0.25ppm and Nitrite Under 1ppm – If Yes, add full Ammonia dose and continue daily testing. You may have to do this a few times.
Is Ammonia and Nitrite Zero – If Yes, Your cycle is finished. Do a large water change and you can now add fish.
If Ammonia and Nitrite read anything else wait and repeat this step every day.
 
Last edited:
Stage 2 - Testing for “Snack Dose”, Test Ammonia every 3 days
In TwoTankAmin's orignal, at this stage testing is every 2 days not every 3. And if you want to stick with the original timetable, it's then

When Ammonia has been zero for 2 tests in a row (6 days with 2 tests)
"When ammonia has been zero for 2 tests in a row (4 days with 2 tests)"

That's the only difference (apart from losing a lot of words) between this and the original that I can see.
 
In TwoTankAmin's orignal, at this stage testing is every 2 days not every 3. And if you want to stick with the original timetable, it's then


"When ammonia has been zero for 2 tests in a row (4 days with 2 tests)"

That's the only difference (apart from losing a lot of words) between this and the original that I can see.
Thanks will edit now.

I think I had it like that to begin with and then changed it 3 days for some reason. Edit: Yeah I originally had some extra steps in and I think when I cut them out and condensed it down I missed that it went from 3 days to 2 days then to every day. Thanks again.
 
So the main sticky for Fishless cycling is great but it suffers a little from information overload and that makes it hard for some to follow the instructions. I thought I would have a go at a "condensed" version. This is in no way meant to replace the original instructions but just act as a quick reference in addition to them.

Please do point out any issues or mistakes I may have made. Putting this together while waiting on installs to finish so had to jump in and out of it a few times.

Quick Reference - Fishless Cycle
First you should fully read the link below. This explains in detail why we need to do a fishless cycle and how. These instructions are meant as a quick reference and supplement to the original thread.

Original Fishless Cycle Thread

Day 1 – Dose Ammonia to 3ppm. Use https://fishforums.net/aquarium-calculator.htm to work out how much Ammonia to use. After 30 minutes, test the tank water for Ammonia to make sure it is around the 3ppm range. Make a note of how much Ammonia you used. Now wait 2 more days before starting "Stage 1 - Firsts Tests".

Stage 1 - First tests Test Ammonia and Nitrite every 3 days.
Is ammonia under 0.75 ppm and Nitrite over 2ppm?
If No repeat this step in 3 days.
If Yes Add the same amount of Ammonia as you added on Day 1 and go to “Stage 2 – Snack Dose”.

Stage 2 - Testing for “Snack Dose”,
Test Ammonia every 2 days – You are now looking for Ammonia to go to zero. When Ammonia has been zero for 2 tests in a row (4 days with 2 tests) you need to add a “snack dose”. This is 1/3rd of your original dose. You only need to do this “snack dose” now, once you have done it go on to “Stage 3 - Daily Testing”.

Stage 3 - Daily Testing – Test Ammonia and Nitrite.
Is Ammonia Under 0.25ppm and Nitrite Under 1ppm – If Yes, add full Ammonia dose and continue daily testing. You may have to do this a few times.
Is Ammonia and Nitrite Zero – If Yes, Your cycle is finished. Do a large water change and you can now add fish.
If Ammonia and Nitrite read anything else wait and repeat this step every day.
Thank you, this is EXACTLY what I needed!
 
Thank you, this is EXACTLY what I needed!
No worries, glad it helped. The original post has tons of great info and covers all the finer points and what can go wrong. Once you have read that though it is easier to just have "when this happens do this, if not keep doing this".

Just maybe give this a day or two to sit though and let anyone else pick any holes in it that might exist. I wrote it in free minutes while at work so it is entirely possibly I missed something or made a mistake as I was going in and out of it. I did go through it several times but sometimes when you write something you go blind to mistakes that others will be able to see easier.
 
No worries, glad it helped. The original post has tons of great info and covers all the finer points and what can go wrong. Once you have read that though it is easier to just have "when this happens do this, if not keep doing this".

Just maybe give this a day or two to sit though and let anyone else pick any holes in it that might exist. I wrote it in free minutes while at work so it is entirely possibly I missed something or made a mistake as I was going in and out of it. I did go through it several times but sometimes when you write something you go blind to mistakes that others will be able to see easier.
Exactly, I love the original post but once you know all of the other stuff you kinda just want to review the basics of the cycle to get the "know-how". I am going to start the cycle today, most likely....
 
Thanks for the simplified version! My tank just finished cycling after only 3 weeks. I must have been lucky with 3 weeks. The one you made didn't hurt my brain as much lol.
 
Obviously a useful post.
Just a couple of probably minor points...
  • Given the importance of dosages, I'd suggest that any calculations of the aquarium refer to the actual volume of water, as opposed to that of the tank. There'll be a difference.
  • Sources of the ammonia would be helpful.
 
Obviously a useful post.
Just a couple of probably minor points...
  • Given the importance of dosages, I'd suggest that any calculations of the aquarium refer to the actual volume of water, as opposed to that of the tank. There'll be a difference.
  • Sources of the ammonia would be helpful.
I thought a lot about putting more information in. However that is all in the original thread which should most definitely be read first. I wanted to keep this as clear and simple to follow as possible.

The idea is you read the other thread, get all the information on the how and why and then can use this as your cycling checklist to see what stage you are at and what to do next.
 
I thought a lot about putting more information in. However that is all in the original thread which should most definitely be read first. I wanted to keep this as clear and simple to follow as possible.

The idea is you read the other thread, get all the information on the how and why and then can use this as your cycling checklist to see what stage you are at and what to do next.
Understood...but the Ammonia sources are well out of date and, given that we're talking about cycling a new tank, the opportunity is there to accurately measure the volume of water in the tank, rather than some relatively vague percentage and subsequent math.
 

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