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Filter cycling?

i'm not saying i would add fish without cycling first, what i am saying, is that if you are not adding ammonia, compost, or ada soil, then you are not really cycling the tank, and once you add fish that will effectively be the propper beginning of your cycle process.

If i am wrong or this information is out of date, i would really like to learn what has changed in the understanding of cycling with plants and substrate in the tank.
 
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I've just ordered my tank - Fluval Spec V, I'm intending to wait until mid this month - next month to get the substrate and plants, is it possible to get my filter cycling in the mean time?

I am going to be jumped at as usual because of saying that again....I've cycled with ammonia many times. One of my old tanks was first cycled empty with filters and ammonia, then I added the substrate and plants and fish almost at the same time, never read any ammonia or nitrite despite getting stocked fully. I can't tell you what type of microbes develop while cycling with ammonia, but whatever they are, they keep going strong when fish are added....

The trick about ammonia cycling is not to add any more than 3ppm. Do not add anymore ammonia until the initial dose has gone down to zero, only then re-dose. Do not let the KH drop to zero, do water changes if needed which will naturally bring it up. Do not let nitrites get out of hand during the nitrite stage, do water changes to bring them back down and re-dose ammonia when it gets down to zero. Follow this until the ammonia dose of 3ppm and subsequent nitrites have gone down to zero in 24hrs. It takes 3 weeks, in worse case scenario 4 weeks. Do a 100% water change. Then stock the tank fully with whatever you want providing your new soil does not leach ammonia also...
 
But why?
It has been established that you don't need to add ammonia to a planted tank for the cycle to take place.

The OP's tank is a new tank. They'll be waiting for substrate and plants, one might as well cycle the tank till then.
The power of plants in a new set up is exaggerated....You've got to go really slow on stock and you have to make sure your plants are growing really well before adding stock, a lot more complicated and unforgiving if you have fish, and get the plant part wrong.....
 
I read the threads that darrel posted and i see merits to the concept, but in my opinion without a propper seed to simulate the bioload of the tank when stocked, you are not actually cycling the tank it just goes against everything i have learned about fishkeeping, and when you introduce a bioload to the tank it will result in a lack of capacity in the bacteria that are present in the aquarium(substrate filter and plants), the plants will do a good 50% of the work for you, as long as they are mature and have developed some good roots, which can take a week onwards, but i am not confident in their ability to make up the shortfall, and large water changes would be a necessity.
 
I am not disputing Darrel's information. I just think it is a speculation to say that an ammonia cycled tank develops the wrong type of microbes, especially considering anecdotal evidence/experience pointing to the contrary. Also, no-one knows what the type of established bacteria/archaea is in their particular tanks.

However, no matter how you call it or decorate with words, a planted soil tank, with ammonia leaching from the soil is pretty much an ammonia fishless cycle, with that difference you can't control the levels of ammonia.....

Between the soil leaching ammonia, taking up huge amounts of oxygen due to decomposition of organics and plants not yet being established, I am pretty certain a lot of people's initial fish didn't last long after that....especially if the tank was started from scratch with new filters....If you start an inert substrate planted tank, the only back up are the plants. Some people take up a year to master plant growth.....It is easy to say from the perspective of experienced plant keepers that all you need is plants and water....

There's one of my old tanks I had just cycled with ammonia and added kuhli loaches to it. This was happening 5 years ago. It was not a new tank at the time but the original population and filtration was moved to another tank so I ended up cycling this one with ammonia.

As you can see on the video, I had placed a few plants in there at the start but the light over the tank was way too low to grow anything at all besides anubias, so the plants packed bags eventually.The kuhli loaches were a new purchase I added straight after cycling the tank, and are still alive 5 years later. I had only cycled it for 3 weeks empty, with ammonia.

 
There are other cheaper sources of ammonia that work well.
https://web.archive.org/web/20160314022344/http://skepticalaquarist.com/fishless-cycling
Its a real shame this site has gone as it was a really good source of "manufacturer free" & practical information.

Also if you have to add fish to a new uncycled tank, like my mate had to when his tank split, emptied all water onto floor and filter with no cooling water burnt out, either do daily water changes or use something like Prime/AmQuel to remove ammonia & nitrite daily. Works well, though difficult to test for ammonia due to interference from Prime. Eventually you do get positive nitrate results indicating it is all working.
 
On a scientific level:

Digestion of ammonia-oxidizer SSU rDNA with five restriction enzymes showed that a high ammonium level resulted in a great community structure change that was reversible once the ammonium concentration was returned to its original level. The smaller changes in community structure brought about by the two pH extremes, however, were irreversible.

As for toxic ammonia levels, same study says the following:

Nitrifying bacteria exhibit different substrate concentration sensitivities (26). Media containing low substrate concentrations (10 mg of NH4+ liter−1) can give larger most-probable-number counts of ammonia oxidizers than media containing higher NH4+ concentrations (6, 26). Also, ammonia oxidation is inhibited at high substrate concentrations. The growth rates of Nitrosomonas spp. cultures were reduced in the presence of 1,050 to 2,800 mg of NH4+-N liter−1

In environments with high inputs of ammonium, such as wastewaters, biooxidation of this substrate increases the oxygen uptake and lowers the pH. Such modifications of the environment not only affect the production of nitrite and nitrate but can also select a different nitrifying community that is perhaps specialized for these new conditions.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC106468/

So basically, the change in nitrifying microbes was brought by pH extremes(irreversible) and not by high ammonia levels(reversible). Plus the extremes in ammonia mentioned

Hence in a fishless cycle it is important to never let the KH and thus the pH drop. Anyone that has done enough fishless cycles knows nitrification stalls when that happens. According to the above study, it doesn't just stall but totally different nitrifying bacteria gets established...Problem is, you're still going to use your clean tap water for water changes, so not letting the KH going down to zero and pH cras while cycling is the way to go....Even without knowing the science behind it, fishless cycling fish keepers have come to the same conclusion...
 
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Hi all,
The problem with doing it for longer than 2 weeks and not adding fish if you are not adding ammonia, is that the plants and filter bacteria will exhaust their resources and you get a "dip" before you add fish, which can lead to the filter bacteria dieing off due to a lack of "food" for want of a better term.
This is really the point, you always sources of ammonia in the aquarium, as proteins are denatured they are split into their constituent amino acids and as these are further degraded ammonia is released. Fish are an obvious source of ammonia, but chlorophyll is also protein rich, and decomposition processes will release this. Fixed nitrogen (so nitrogen that isn't in the form of N2 gas) is a scarce and patchy resource in natural ecosystems and the organisms that rely on it are adapted to a "boom and bust" existence.

Have a look at <"New High Tech Setup...">
i'm not saying i would add fish without cycling first, what i am saying, is that if you are not adding ammonia, compost, or ada soil, then you are not really cycling the tank, and once you add fish that will effectively be the propper beginning of your cycle process
This is still looking at ammonia as the most important factor in biological filtration, but it isn't oxygen is, scientists talk about Biochemical Oxygen Demand (BOD) because it quantifies the total amount of pollution. Cycling is an ongoing process, and it never really starts or stops, the more complex ecosystems are the more resilient they become. If you think of cycling as a web, rather than a linear process (with a switch from "non-cycled" to "cycled"), it becomes easier to visualise whether systems are likely to maintain water quality.

If we look at BOD values, clean rivers have a 5 day BOD value of about 1 mg/L, and at 8mg/L they are heavily polluted, and raw sewage averages about 400mg/L. You can only get about 8 mg/L of oxygen into aquarium water (warm water holds less dissolved gases) so you can see that if you want to treat the ammonia in sewage that, as well as a community of nitrifying organisms, you need to constantly replenish the oxygen. We can actually treat sewage with a relatively small volume of bacteria if we get enough oxygen into it. Normally we add air (~21% oxygen), but we can improve the efficiency of nitrification by adding pure oxygen (O2) (like plants do via photosynthesis).

A relatively small wet and dry trickle filter has much more nitrification potential than a big canister filter, mainly because the amount of oxygen that enters the canister is finite, and it can't be replenished in a sealed container. Wet and dry trickle filters have huge gas exchange surfaces, and that is really why they are so good. You can improve a wet and dry trickle filter by planting it, and there is a lot of scientific work on this for effluent treatment using <"Constructed Wetlands">.

You can make your canister filter even less efficient by stuffing it with media so that it can fulfill the anaerobic denitrification arc (converting NO3 to N2 gas). I'm not even going there, that is a sure recipe for eventual disaster
and you have to make sure your plants are growing really well before adding stock,
but i am not confident in their ability to make up the shortfall, and large water changes would be a necessity.
These are important points, plants only work to improve water quality when they are growing. Submerged plants are CO2 limited, but a floating or emergent plant aren't, when you add a floating plant it starts working straight away. Floating plants are widely used in <"sewage treatment etc."> in warmer regions, because of their high potential growth rates.
In environments with high inputs of ammonium, such as wastewaters, biooxidation of this substrate increases the oxygen uptake and lowers the pH. Such modifications of the environment not only affect the production of nitrite and nitrate but can also select a different nitrifying community that is perhaps specialized for these new conditions.
I just think it is a speculation to say that an ammonia cycled tank develops the wrong type of microbes, especially considering anecdotal evidence/experience pointing to the contrary. Also, no-one knows what the type of established bacteria/archaea is in their particular tanks.
According to the above study, it doesn't just stall but totally different nitrifying bacteria gets established..
That is right, but I'm pretty sure the community we want is the community is specialised for these new conditions.

I don't know what organisms I have in my tanks, I don't know what the BOD is and I don't know what the exact water parameters are, and nor does any-one else who keeps an aquarium. I could potentially get a snap shot of BOD, dissolved oxygen and reasonably accurate chemical parameter values because I have access to analytical kit in the lab., but even that would only be a snap-shot, and I don't have access to any RNA analysis techniques.

Before the development of RNA libraries we were reliant on culturing bacteria (from sewage treatment etc) to find out what organisms were involved in nitrification, which led to many of the assumptions about aquarium cycling that we now know to be incorrect. It isn't surprising, if you look at raw sewage it is a very different medium, from even very polluted, aquarium water. Dr Tim Hovanec talks about this is in <"Bacteria revealed">, and there are a number of papers specifically on the nitrifying organisms in aquarium filters which suggest that their assemblage shows a fluid response to varying ammonia loadings, with a stable core of archaea and an ever changing cast of nitrifying bacteria. This is described in <"Freshwater Recirculating Aquaculture System Operations Drive Biofilter Bacterial Community Shifts around a Stable Nitrifying Consortium of Ammonia-Oxidizing Archaea and Comammox Nitrospira">.

cheers Darrel
 

A nice read. Thanks. There is a bit more on Nitrite oxidising bacteria below, also species dependence on pH.
http://aem.asm.org/content/82/6/1838.full.pdf

If you think of cycling as a web, rather than a linear process (with a switch from "non-cycled" to "cycled"), it becomes easier to visualise whether systems are likely to maintain water quality.

Well I don't think of a cycle as a linear process, neither am I one of the people thinking my cycled tank has zero ammonia :)

I can't access the full article, just a portion, but this is what it says about the cycling phase "being over" in relation to recirculating aquaculture systems(RAS)

This study showed that bacterial activity was not a straightforward predictable parameter in the waterphase as e.g. nitrate-N would be in identical RAS, and showed unexpected sudden changes/fluctuations wthin specific RAS. However, a bacterial activity stabilization phase was observed as systems mature and reached equilibrium, suggesting a successive transition from fragile to robust microbial community compositions.

http://orbit.dtu.dk/en/publications...ms(adcf8667-f52d-487f-9b1d-0b8c0812ca9f).html
 
These are important points, plants only work to improve water quality when they are growing. Submerged plants are CO2 limited, but a floating or emergent plant aren't, when you add a floating plant it starts working straight away. Floating plants are widely used in <"sewage treatment etc."> in warmer regions, because of their high potential growth rates.

Yes, that's pretty much the best way to utilise plants. I am a total convert of emersed plants via submerged due to CO2 and even light limitations.
If I place the emersed growth I have over my mini pond inside the tank, the plants will probably fill it right now, and are more than likely higher than the tank itself. So I'd call this big plant mass. But being outside the water, the maintenance they need is almost zero...No fuss, and happy fish. I don't have to worry about gassing my fish with CO2 either...My plants also have access to direct natural light...
 
Hi all,
There is a bit more on Nitrite oxidising bacteria below, also species dependence on pH.
I don't know much <"about Nitrotoga spp">, other than they are more abundant in colder temperatures. I would suspect that we've only touched the surface with microbial diversity, and that the more people look the more they will find.

I don't have access to "Bacterial activity dynamics in the water phase during start-up of recirculating aquaculture systems" either. It is another novel technique for investigating microbial diversity using enzyme activity.
suggesting a successive transition from fragile to robust microbial community compositions
It is back to "good things come to those who wait" I would love to know what the microbial dynamics of an aquarium system are, and the time scale for the development of a robust microbial community, and I expect that some-one will attempt to quantify these for aquaculture, probably for salmonid culture, due to their high water quality (particularly dissolved oxygen) requirements.

cheers Darrel.
 
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