How to Cycle a Tank Without Fish | Part 1 Cycling Experiments

Find out how to do a fishless cycle using ammonia in a freshwater tank and how long it may take.

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0:00 Quick overview of the aquarium nitrogen cycle
0:45 Why aquarium cycling is so important
1:22 How the cycling experiments were conducted
1:51 Method 1 – fishless cycling with ammonia only
3:02 Method 2 – fishless cycling with ammonia and bottled bacteria

#girltalksfish #nanofish #plantedaquarium

[alineh]

OMG... That's the longest poop I've ever seen!

[shesellsfish]

I love how deep you dive into all your experiments.
I'm still so proud of how far you've come in your fish career. I always knew way back when, that your channel was something special and so were and are you!
👍💓👍

[NORIaquaCh]

I really appreciate your time to upload in 60FPS. It makes you look so much more 'live'. Thank you!

[christopherfassett]

Love the video. I have a few comments/questions.

1) Did you add any fertilizer? Nitrifying organisms need trace elements to grow too, occasionally the cycle can stall because they don't have the correct available nutrients to reproduce. A teeny bit of Easy Green would prevent that.

2) One of the issues with bottled bacteria is that no producer to my knowledge includes ammonia oxidizing archaea. Fairly recent research on the subject has demonstrated that archaea is the heavy lifter when it comes to oxidizing ammonia in the aquarium (especially freshwater aquariums), and not the nitrosonomas bacteria that was believed to be the primary oxidizer in the past. In particular, nitrifying archaea thrive in low ammonia environments while nitrosonomas bacteria thrive in higher ammonia environments. The reason this is particularly relevant to this test is that when all you have in the tank is bacteria, lower amounts of ammonia, like 2 ppm, a) might not be enough to stimulate population growth in the bacterial colonies and b) amounts under a certain threshold, like 0.25 ppm ammonia, might not even be enough for the bacteria to oxidize and they may instead go dormant or die, resulting in a stalled cycle. It seems like there's a good chance that this is what happened with the second method

3) I'll bet the tank cycles much faster with plants for two reasons: a) fertilizer will ensure that the nitrifying organisms have no mineral deficiencies and b) the plants will have come from a cycled environment. Even if they were grown emersed they'll have both archaea and bacteria living on them and will act like cycled media to seed the aquarium. The same thing happens with fish-in cycling, the fish itself has nitrifying organisms living on it and it seeds the aquarium filtration. I cycled a 45 gallon aquarium in 3 days from a single bioring once. I know lots of people have demonstrated that you can use used filter media to cycle and aquarium but I'd love to see some experiments to show how little of a seed you can get away with. One bioring? A cubic inch of sponge? A single plant? a pebble of gravel? Some people have suggested that a spoonful of soil from any half-fertile bit of ground outside works as a seed too. If that's true, then why on earth are we buying bottles of incomplete bacteria?

4) Last comment: you touched for the briefest moment on one of the most misunderstood topics in the freshwater hobby: pH. Most of the time pH isn't very important but when it comes to the nitrogen cycle it's super important. That chart shows how it affect toxicity but also, nitrifying bacteria are only capable of peak growth between 7.6 and 7.8. Anywhere outside that range and they will grow more slowly (we don't yet know the peak growth environment for ammonia oxidizing archaea but it seems to be in the same vicinity, though perhaps a little lower, like 7.5ish). Below 7 and it's going to take significantly longer. Below 6.5 and it'll take months. Below 6 and it may never happen at all, and a pH below 5.5 kills them. For that reason, while chasing pH with fish in the tank is generally a terrible idea, whe performing a fishless cycle, I recommend using either distilled vinegar or baking soda (to lower or raise pH, respectively) to get the system to the optimal growth range. Then when it's cycled, you can just do a few big water changes to bring it back to whatever's normal for your location and you're good to go.

Great to see you doing practical testing for this topic. I love your videos in general. Cheers!

[EricLabelleUX]

Saturday mornings with GirlTalksFish and coffee! Perfect!! Thanks for all your hard work! :)

[RyanRoux]

This video is perfect timing. I'm about to setup a new aquarium and I want to give fishless cycling another shot. I've only tried it once before using fish food, but with results similar to your second test. I can't wait to see part 2.

[lurklingX]

can i just say HOW MUCH i appreciate you for doing these testings, methodical, and sometimes long? i mean... it's really priceless and the amount of work that goes in and the TIME and how much time you can save us is just really special and helpful.

[raveG]

There is a lot of aquarium metaphysics out there, so kudos, Irene, for always being so thorough. I love your experiments because they help everyone (especially beginners) to reduce the guesswork.

What was your hypothesis behind the first experiment? Where should the bacteria come from?

I cycled three tanks following Dr. Tim's guide and was quite successful. I want to make two remarks: First, the method is much faster when you work with already established media, gravel, plants, etc. As you mentioned, aquariums are micro eco-systems that are affected by many variables and not just what comes out of a bottle. Forget the heater during cycling--add weeks to the process. Second comment: always check your checker. In my last tank (only a few months old) I thought I did everything right but I just couldn't get below 0.25 ammonia. I contacted Seachem asking about the batch of Stability I had, then bought different bacteria, tested like a maniac, but it just wouldn't go down. Then it dawned on me that my only point of reference is my API test kit (the one you use). It wasn't expired but I bought a new one anyway, and guess what: my older kit always showed a slightly green tinge while the new one was yellow. I sent photos to Seachem showing them how even distilled water tested positive for ammonia. They doubted what they saw, asking where I "sourced" my distilled water (Target). So, now, when I need to be sure, I always have a control test tube with RODI water. That doesn't apply to you experiments, I know, but if you take a scientific approach to the hobby that is something to keep in mind.

[Sabriel]

I learned from Cichlid Forum that water changes are essential to fish less cycling with straight ammonia. Small water change every day and ammonia dosing every other day. Seems counterintuitive, but it's worked on the last two tanks I've cycled! Can't wait to see about other options though!

[adso]

These experiments are so useful.. Honestly thankyou thankyou.. Nothing is 100% but these sort of results are much more factual than an anecdotal comment on a forum or a video.

Those failures you speak of imo are fantastic.. Gives you a realistic expectation.. And might prevent a new fish keeper from adding fish too early (which is what I did on my 1st tank).

I actually think the solution might even be a little from video 1, 2 and 3 if possible!

[DavidTorres-fblh]

I did my fish less cycle with only plants (thanks to you ) but still added an established filter once I added a fish . I’m about to add the rest of my center piece fish this weekend 😁

[short_bar]

A year long experiment! Thanks for doing this, excited for the next parts!

[jengsaquatics]

Looking at your chart, your ammonia was almost gone at week 7, until you added another 2ppm of ammonia. Spikes in ammonia can actually stall and prolong a cycle, which is what I think happened here. Don't give up! Worth trying it again. This is a marathon, not a sprint :) I've used this very same method (same Dr. Tim's) without adding any starter bacteria, at 4ppm and had wonderful success. I did do water changes to keep my nitrates where I would want them once fish were in. I noticed the higher my nitrates got, the lower the ph was getting. I treated it like a fully stocked tank and did my water changes while feeding with ammonia every time it hit 0ppm. It did slow the cycle down, but did pick back up and headed in the right direction. EVENTUALLY, my tank was able to process 4ppm in 24 hours (doing water changes to lower nitrates). Once I saw it was happening on a consistent basis, I did a big water change, added my fish and had no issues at all. Notice how long it took your initial 2ppm to get to 1ppm (with the addition of starter bacteria...2 weeks). Notice it only took 1 week to go from 2ppm to 1ppm (week 8-9) without adding starter bacteria? You were almost there! Don't give up :)

[angiemoore]

Thank you so much for all of the hard work that you put into these videos. Sharing this information is so valuable to the hobby

[mastermarkus]

Oh my god, those fish have huge poops. I'm not used to seeing that because I keep tetras (fairly small) and bottom-dwelling fish like corydoras and dwarf plecos.

[alexathehuman]

Can’t wait for the next part 😊 my favorite way to cycle is with starting with plants and snails!

[waynetalbot]

Can't wait for part 2, I too am just about to cycle a 260ltr planted tank, with a sand substrate, so my plants will be water column feeders.I enjoy your video's keep up the great work.👍👍👍

[ForgotnBurrito]

Very interesting tests! I’m excited to see the next video. I’m about 8 weeks into cycling currently, so this is helpful info

[pleaseleavesarayualone]

Hello irene! Great video as always! This is sure to help A LOT of beginner fishkeepers!😀😆😆😄

[James-yvqq]

My aquarium just finished its cycle yesterday! On to the fish store!!