Cycling a walstad tank without a filter

After setting up two low-tech/walstad tanks with filters running, my next adventure is a heater-less/filter-less walstad in my 60L.

Where understanding starts to back down is the cycling process for such a tank. As I understand it Diana Walstad says, in her book, that with a densely populated walstad tank there is no need for cycling as the plants/soil will soak up the ammonia/nitrite.

So is it a simple case of doing what I’ve already done in my other tanks, just without a filter, waiting a week to let everything settle and ensure there are no spikes caused by the soil, and then adding fish?

There’s no need to dose up to 2ppm of ammonia to ensure it’s processed within 24 hours etc?

 

Add a few dry leaves and induce water movement, with a filter (without media) or airstone, to speed things up significantly. All else, let nature take care of itself.

After some time, you can take the filter or airstone out....but, well, I recall we discussed this before, I would leave the filter in, with or without media. Or at least apply an airstone to ensure crystal clear water surface.

But no drama if you go for still water.

 

We did speak about it before I was genuinely interested in running a filter-less tank, just as an experiment.

I’m just not overly clear on how a still water tank cycles, does it still need dosing?

 

You don't need to dose ammonia. It will occur naturally in a rich soil and planted tank. A few dry leaves help to speed things up. The plants, oxygen and microbes take care of the rest. Plants, including the rhizosphere, create a huge oxygen rich area for microbes.

Still water moves (Brownian motion); thanks to biochemical processes (such as oxygen production), light, ambient temperature and organisms that move (even the tiniest by way of a flagellum).

Fishlore is not the best place to discuss "nature tanks". It's primarily about fish keeping first and foremost. And keeping tanks bare and clean. Liquids are used to get cycling going. (But hurry, my fish arrive next week!) A whole different mindset, a different approach.

 

There’s no need to dose up to 2ppm of ammonia to ensure it’s processed within 24 hours etc?

I would think you'd still need to dose 2ppm ammonia, just to make sure that even if not via nitrification, the other methods combined would still be able to handle 2ppm ammonia/day.

 

I would think you'd still need to dose 2ppm ammonia, just to make sure that even if not via nitrification, the other methods combined would still be able to handle 2ppm ammonia/day.

Doesn't make any sense in a Walstad type of tank. Then again, plants will love it. So go ahead.

 

Doesn't make any sense in a Walstad type of tank. Then again, plants will love it. So go ahead.

I mean the point is just that in a Walstad tank, all these other things consume ammonia instead of nitrifiers right?

The purpose of dosing 2ppm ammonia to test the cycle is to make sure the nitrifiers is able to handle ammonia produced by a full stock daily. So would it not be the same for a Walstad tank, just that we are testing to make sure the non-nitrifiers, rather than nitrifiers, in the tank is able to handle said 2ppm ammonia?

 

I know you love cycling. Me to, on a bike.

I refrain from discussing "ammonia based - test kit cyclings" versus "plant/microbe filtration". Been there, done that; always ending up in entrenched positions.

So feel free to advice devsi. I'm out.

 

I know you love cycling. Me to, on a bike.

I refrain from discussing "ammonia based - test kit cyclings" versus "plant/microbe filtration". Been there, done that; always ending up in entrenched positions.

So feel free to advice devsi. I'm out.

If it seemed like I was just trying to cause trouble or rile you up or anything, I apologize, that was not the intention.

I really want to ask, because personally I have yet to look at the Walstad method in detail. So my question is borne genuinely out of curiosity. The idea is that we have plants and stuff taking care of ammonia in lieu of nitrifiers, and I assume the expectation is the performance is the same re: ammonia consumption. Is that right? If so I would really like to know if there is a reason why the ammonia-dosing, or even ghostfeeding or whatever, would not be something to consider, to test the tank's capacity to handle ammonia?

 

I was quite disappointed to see this conversation end during a healthy discussion, especially as a lot of the questions Azedenkae raised were also in my brain.

To my uneducated brain, I can't understand why you wouldn't want to dose a walstad tank to 2ppm to ensure the tank can actually handle the load. If the whole philosophy is that the plants/soil will handle the ammonia/nitrite, then it should also be able to handle the dosing?

FWIW, I don't think anybody was being disrespectful or argumentative, I'm assuming the reaction has happened due to prior experiences of discussing this on FishLore?

ruud, I'd love to continue the discussion and understand more and I believe that was Azedenkae's intention as well.

Open discussions are always favourable, as it helps everybody, but if it helps to know there won't be any railroading, we can move the discussion to a private message group, if that suits you both better?

 

Well, my bad. Apologies.

Nothing wrong with cycling via the ammonia dosing route, with heavy reliance on a filter, and using a test kit to measure the cycling endpoints.

In a heavily planted tank / "nature tank" it is just not needed. Adaption takes place, for sure, but the "fishkeeping route of cycling" can be put aside. Healthy plants that are already adapted to aquatic conditions is required though. Anyways, I'll write a post about it in this thread, add a couple of references, and share my personal experiences with setting up new scapes.

To be continued this weekend - busy days and evenings ahead.

 

No apologies needed, at least not from my side

I look forward to your post, when you have time to write it! Thank you!

 

OK, so I've given myself 30 minutes off . Here goes:

If you don’t have plants or just a few, one should follow some sort of ammonia type of cycling, I guess. But it is never ideal. As I oftentimes argue, a lot of things go fine in tanks, not “because of”, but “despite of”. Despite stimulating certain bacteria to grow by dosing 2 ppm ammonia, the right microbes, mainly archaea and nitrospira bacteria, will establish themselves anyhow to take care of "protein metabolism" by organisms. As a matter of fact, growth of nitrospira is likely restricted by the usual ammonia levels dosed for cycling.

Rapid advances in DNA sequencing is starting to make all this clear.

Let's turn to planted tanks. In planted tanks, cycling is oftentimes referred to as “silent cycling”. Not sure why. I think to position it from “traditional, ammonia-dosed cycling in non-planted fish tanks with heavy reliance on filters”.

In planted tanks, two things happen:

• Plant growth. Probably the aspect most underestimated by the traditional fish keeping hobby. Plants take in all forms of fixed nitrogen and are huge net producers of oxygen. The latter being the determining factor in nitrification.
• The plant/microbe complex. Diversified patches of different microbial species, nutrients, waste and oxygen produced by plants, including the rhizosphere, is where most of the nitrification takes place.

Both plant growth and plant/microbe filtration take care of ammonia much better than any filter added to a planted tank which relies solely on (partly similar) microbes and less oxygen. Hence, in planted tanks, filter media is not really that important. Perhaps not even desired.

So how to go forward with your Walstad project?

If most of the plants have just been purchased, they need to adapt to aquatic life first. Not taking account of this can result in a false start. Plant abundantly (“Walstad”) and observe your plants. Once you get the impression plant growth is occurring, you can introduce fish and / or inverts. 4 weeks is a ballpark figure.

Dosing ammonia is irrelevant and perhaps even disturbing given the levels. Focus solely on plant growth.

Personally, I never bridge the 4 week gap, provided what I scape is taken from a tank in similar conditions. If someone would refer to this as “instant cycling”, I won’t argue. Myself, I don't call it cycling at all. The microbial community is very responsive and hetergeneous. And in combination with plants, makes for a very stable and resilient system. Unlike non-planted tanks.

Once your tank is established (plants are healthy and growing), you should also welcome the decaying part of plantlife for sake of humification, amongst others. But enough for now.

A few references:

• Aquarium Nitrification Revisited: Thaumarchaeota Are the Dominant Ammonia Oxidizers in Freshwater Aquarium Biofilters
• Kinetic analysis of a complete nitrifier reveals an oligotrophic lifestyle - Nature
• Freshwater Recirculating Aquaculture System Operations Drive Biofilter Bacterial Community Shifts around a Stable Nitrifying Consortium of Ammonia-Oxidizing Archaea and Comammox Nitrospira
• https://www.sciencedirect.com/science/article/abs/pii/S0043135498004394
• Archaea and the origin of eukaryotes - Nature Reviews Microbiology

 

OK, so I've given myself 30 minutes off . Here goes:

If you don’t have plants or just a few, one should follow some sort of ammonia type of cycling, I guess. But it is never ideal. As I oftentimes argue, a lot of things go fine in tanks, not “because of”, but “despite of”. Despite stimulating certain bacteria to grow by dosing 2 ppm ammonia, the right microbes, mainly archaea and nitrospira bacteria, will establish themselves anyhow to take care of "protein metabolism" by organisms. As a matter of fact, growth of nitrospira is likely restricted by the usual ammonia levels dosed for cycling.

Rapid advances in DNA sequencing is starting to make all this clear.

Let's turn to planted tanks. In planted tanks, cycling is oftentimes referred to as “silent cycling”. Not sure why. I think to position it from “traditional, ammonia-dosed cycling in non-planted fish tanks with heavy reliance on filters”.

In planted tanks, two things happen:

• Plant growth. Probably the aspect most underestimated by the traditional fish keeping hobby. Plants take in all forms of fixed nitrogen and are huge net producers of oxygen. The latter being the determining factor in nitrification.
• The plant/microbe complex. Diversified patches of different microbial species, nutrients, waste and oxygen produced by plants, including the rhizosphere, is where most of the nitrification takes place.

Both plant growth and plant/microbe filtration take care of ammonia much better than any filter added to a planted tank which relies solely on (similar) microbes and less oxygen. Hence, in planted tanks, filter media is not really that important. Perhaps not even desired.

So how to go forward with your Walstad project?

If most of the plants have just been purchased, they need to adapt to aquatic life first. To not take account of this, can result in a false start. You need to add plants that have already been adapted to aquatic life. Plant abundantly (“Walstad”) and observe your plants. Once you get the impression plant growth is occurring, you can introduce fish and / or inverts. 4 weeks is a ballpark figure.

Dosing ammonia is irrelevant and perhaps even disturbing given the levels. Focus solely on plant growth.

Personally, I never bridge the 4 week gap, provided what I scape is taken from a tank in similar conditions. If someone would refer to this as “instant cycling”, I won’t argue. Myself, I don't call it cycling at all. The microbial community is very responsive and hetergeneous. And in combination with plants, makes for a very stable and resilient system. Unlike non-planted tanks.

Once your tank is established (plants are healthy and growing), you should also welcome the decaying part of plantlife for sake of humification. But enough for now.

A few references:

• Aquarium Nitrification Revisited: Thaumarchaeota Are the Dominant Ammonia Oxidizers in Freshwater Aquarium Biofilters
• Kinetic analysis of a complete nitrifier reveals an oligotrophic lifestyle - Nature
• Freshwater Recirculating Aquaculture System Operations Drive Biofilter Bacterial Community Shifts around a Stable Nitrifying Consortium of Ammonia-Oxidizing Archaea and Comammox Nitrospira
• https://www.sciencedirect.com/science/article/abs/pii/S0043135498004394
• Archaea and the origin of eukaryotes - Nature Reviews Microbiology

Thank you for your response and really diving deeper into your viewpoint.

To preface my questions below, I just want to iterate again it is borne entirely out of a place of genuine curiosity, and I'd like to know more. I know I have riled a lot of people here up in the past, I will not get into why or how or for what reasons as that will surely bring in unnecessary issues into this discussion. But I do just want to establish that here I am fully curious.

So, anyways.

Perhaps it might be surprising to you, but I would say I agree with pretty much everything you stated. Including the knowledge that what we establish during the 'normal' cycling process is not exactly what ultimately comprises the biofiltration system, as I have read the same articles you linked (and myself on here have linked the same articles at different times). I do have an argument for cycling with current methods regardless - as while over time the community will be replaced with the 'right' type of nitrifiers, namely archaea as the dominant ammonia oxidizers rather than bacteria, aside from money spent on buying products like bottled bacteria or establish biomedia + pure ammonia, I do think it is fine even if the 'sub-optimal' type of nitrifier performs the ammonia detoxification function, even as over time they are replaced by the 'optimal' nitrifiers. I myself though am very interested in digging into the topic deeper and am raising some funds to purchase a sequencer so that I can do some combined metagenomic + metatranscriptomic studies of my own aquariums. Anyways, I digress however, I don't think this is particularly relevant here.

In fact, I think perhaps we could better outline exactly what is being discussed here. With the 'traditional' method of cycling, dosing 2ppm ammonia is not only to cycle the tank, but to check that it is safe to add fish (at maximum capacity at once if desired). And I think the latter is what both devsi and I are interested in knowing more about, i.e. how to know it is safe to add fish.

In your response, you mentioned relying on visible signs of plant growth as when adding fish is possible. So I want to ask more about this - how do we know that the plants (and other organisms) in the aquarium is making it safe for the fish? Is it like, just a matter of making sure enough plants (and substrate) have been added when say a certain amount of growth is seen? Is it just that plants are so good at uptaking ammonia (I guess depending on the species) that the moment there is growth, that's absolute signs that any level of ammonia produced by the live stock will be handled? Is it a combination of these factors? Or parts of them? Or none of them, and I am entirely off and it is something else entirely?

On that note, you said "[d]osing ammonia is irrelevant and perhaps even disturbing given the levels", can I ask why? Is it because we might be adding so much ammonia it actually harms the plants (i.e. causing 'ammonia burn')?

 

Yes, I get the testing part. I just have to understand its relevance.

Adding 2 ppm ammonia...well, thinking it over, I can imagine it says something about the overall filtration part of the plants/microbe system. If the system is not able to process this amount within a short time frame, what does that say about the tank's conditions. This is the point where I'd need to further investigate.

Further, 2 ppm ammonia is not representative of "Walstad fish stocking"....at least not in my book.

That said, what harm can it do? I think the biggest danger/killer to fish in an aquarium are all sorts of bacterial toxins. Also in relation to KH/GH and oxygen. If fish die in a newly set-up tank, "cycling" is the first thing that pops up in many people's heads. I would be more inclined to look at bacterial toxins, KH/GH and oxygen levels. But not ammonia. A brand new tank still needs to mature before adding fish, though.

If you have a high ph, high temp tank, and higher levels of ammonia than what is oftentimes communicated (because here too, science seems to deviate from the hobby), things can get anywhere from rough to toxic for fish. But again, high ph, high temp, is not what I associate with Walstad/nature/planted tanks in the first place.

Anyways, this is my take. Perhaps explaining my knee-reflex a bit to everything related to cycling, mechanical filters (well, up to a point) and vacuum cleaning. To me the fishkeeping/planted tank hobby is about minimal intervention in order to create microbe diversification and thereby stability and resilience. And gazing at the tank of course.

 

ruud - I just wanted to drop a message to thank you for going into all the detail you did.

I’ve read it a few times, but feel like I still need to read it a few more before I can come up with any sort of response.

Just didn’t want you to think your efforts were in vain, or that I didn’t appreciate them.

 

No problem, no big deal, no need to answer, but thanks .

Let the tank mature for a month or so, when you spot some plant growth, you can conduct an ammonia test if that makes you feel comfortable. If the results are fine, you can add some fish.

 

Sorry, I was away over the last three days attending a conference. Should have at least let you know though.

Adding 2 ppm ammonia...well, thinking it over, I can imagine it says something about the overall filtration part of the plants/microbe system. If the system is not able to process this amount within a short time frame, what does that say about the tank's conditions. This is the point where I'd need to further investigate.

Further, 2 ppm ammonia is not representative of "Walstad fish stocking"....at least not in my book.

I think this may be the key point you raise. Mulling over what I know about what people stock such tanks with, it can certainly make sense.

To be honest, 2ppm is too high even in my books, as even for my fully stocked, heavily fed cichlid tank, I am still only maxxing out at just above 1ppm.

For my other cichlid tank I am hitting closer to 0.25ppm. It is currently understocked though, so there is that.

But I certainly understand where you are coming through here.

That said, what harm can it do? I think the biggest danger/killer to fish in an aquarium are all sorts of bacterial toxins. Also in relation to KH/GH and oxygen. If fish die in a newly set-up tank, "cycling" is the first thing that pops up in many people's heads. I would be more inclined to look at bacterial toxins, KH/GH and oxygen levels. But not ammonia. A brand new tank still needs to mature before adding fish, though.

If you have a high ph, high temp tank, and higher levels of ammonia than what is oftentimes communicated (because here too, science seems to deviate from the hobby), things can get anywhere from rough to toxic for fish. But again, high ph, high temp, is not what I associate with Walstad/nature/planted tanks in the first place.

I suppose that is also true, re: the pH/temp interactions with the balance of unionized ammonia and ammonium. Taking an assumed toxic unionized ammonia concentration of 0.025ppm, even 1ppm total ammonia at a pH of 7.4 and at 30 degrees celcius is not toxic anyways. For a low pH, lower temperature aquarium, one could probably easily reach 4ppm total ammonia or more before there is enough unionized ammonia to be toxic. So yeah, I can really see your point here.

Anyways, this is my take. Perhaps explaining my knee-reflex a bit to everything related to cycling, mechanical filters (well, up to a point) and vacuum cleaning. To me the fishkeeping/planted tank hobby is about minimal intervention in order to create microbe diversification and thereby stability and resilience. And gazing at the tank of course.

I guess at the end of the day, I at least broadly agree with your statements, especially pertaining to a walstad tank. I'd still imagine it would give much more peace of mind to know a tank can handle a certain amount of ammonia. Yes, at lower pH and temperature total ammonia has to get super high, and there is an argument against the likelihood of reaching the point where there is enough unionized ammonia to be toxic, but it is still possible.

I suppose as a cichlid keeper whose aquarium conditions may not be all too similar to a walstad tank (cichlids don't take kindly to plants, even roots of pothos and stuff), all this may not be all too applicable to me as the 'traditional' cycling is still necessary, but I absolutely see why for certain aquariums, i.e. walstad tanks, it is a whole other something else.

But yeah, thanks for answering my questions. It does clarify quite a few things I've wondered about.

 

Alright, I got enough time to sit down and fully read through everything to the extent I understood (mostly) what was being said.

Thank you for the great conversation here!

I just have one follow up question....

Hence, in planted tanks, filter media is not really that important. Perhaps not even desired.

I currently have two walstad tanks; a 120L and a 180L.

The 120 is using an internal Jewel filter without the carbon media seen in the below image (i.e. I'm only using the blue/green/white sponges).

The 180 uses a Fluval 407 with the whole shebang; carbon, biomax, biofoam etc.

In the 120, the plants aren't looking great (I raised a new post for it - Do these plants look healthy?), whereas in the 180 they are thriving such that I am constantly trimming them back and replanting.

I'm assuming that could be because there are different plants in the two tanks, but is there also a suggestion on what type of filter media to use, if it is indeed going to be used?

I like the idea of having my filter running, even if its just as a secondary source, but I'm unsure if any of the filter media could be harming the plants? I think I've heard carbon can be less-than-useful, but I've never had that confirmed so haven't removed it from the fluval,

 

Oops, I just posted something about this: Filter media, which one is better? | Freshwater Aquarium Discussion Forum | 525558

But note: this is solely restricted to nitrification.

Anyways, toss the carbon, regardless, and choose whatever you want. I would see to it, that it doesn't clog easily. So any white floss, I would remove too.

I'll have a look at your post later on.

 

Excellent, thanks for the link! I’ll definitely look into that!

Anyways, toss the carbon, regardless, and choose whatever you want. I would see to it, that it doesn't clog

So no carbon and no floss! Got it! But leave everything else?