# Cycling a planted tank



## Matt1988 (23 Sep 2012)

As titled can anyone link a thread or make a suggestion

Thanks,
Matt 


Sent from my iPhone using Tapatalk


----------



## darren636 (23 Sep 2012)

what exactly do you want to know?


----------



## Matt1988 (23 Sep 2012)

I read somewhere someone said planted tanks aren't cycled the same way normal tanks are I was just wondering what the difference was 


Sent from my iPhone using Tapatalk


----------



## darren636 (23 Sep 2012)

the difference... they call it a silent cycle.  you can cycle a planted tank in exactly the same manner as you would normally- using ammonia and a test kit. this will take 3 weeks.   or you can dump fish in from the start, if your tank is very heavily planted the fish might survive with only minor health issues in the future, or they might die.


----------



## Matt1988 (23 Sep 2012)

I don't think that fair to the fish so ill be doing it with ammonia is it the standard 1-2ppm a day until its used up within the day?

Matt


Sent from my iPhone using Tapatalk


----------



## Tim Harrison (23 Sep 2012)

I think I've mentioned elsewhere in this forum that I've often dumped critters in straight after setting up a new low-energy aquarium. So far I've not had a problem. But I've always been very reluctant to recommend this approach since it may not work so well for others.

I did the same recently when I set up my CO2 injected tank, admittedly I had a cycled filter, the ammonia went up slightly for a couple of days but settled thereafter as near to zero as to make no difference. But then things happen at a much greater rate of knots in a fuel injected aquarium.

But still not absolutely sure what you are after, nevertheless see below maybe this will be of use:

Soil/sediment metamorphosis
Newly submerged terrestrial soil goes through a number of chemical and biological changes before it becomes stable aquatic sediment. During these changes organic matter is broken down to form inorganic molecules, or the nutrients that plants can use; this process is often referred to as mineralization.

Mineralization of a submerged soil usually releases ammonia and other chemical compounds in to the water column where they can reach levels that are toxic to fish and invertebrates; but rarely to plants so it is usually safe to plant a newly set up tank immediately. The use of macrophytes as water purifiers is well documented, so apart from adding instant interest, planting heavily from the outset will help to reduce ammonia and other chemical compounds to non-toxic levels. The plants will also often benefit from the additional nutrient load and CO2 given off during mineralization.

Self-cycling method
I have always found that the ammonia given off during mineralisation is more than adequate to cycle a filter so now is the time to hook one up. This self-cycling phenomenon is in effect fishless cycling but without the hassle of dosing ammonia, or adding fish food and suffering the subsequent consequences of phosphate build up. There is also far less water testing involved. 

Rate of mineralisation
Mineralisation can take up to 2 months to complete, but the actual rate is determined by a number of factors such as the organic content of the soil, water and soil chemistry, and microbial activity. Planting heavily from the outset also helps to reduce the length of time it takes for newly submerged soil to stop giving off ammonia since macrophytes release O2 and organic compounds through their roots which will greatly increase microbial activity, and therefore nitrification and denitrification. The existing bacteria on plant roots will also help inoculate the sediment and perhaps further speed the process on its way. 

Soil equilibrium
Eventually an equilibrium is reached and the soil substrate will actually start to absorb ammonia/ammonium from the water column where it will undergo nitrification. When levels of ammonia, nitrite, and nitrate stabilize within acceptable levels it’s a sign that denitrification is also well under way. If Nitrate levels are still a little high a substantial water change is usually all that is required to make the tank habitable to fish. 

Mutually inclusive processes
Overall levels of ammonia, nitrite, and nitrate always seem to stabilize within acceptable levels quite quickly, often within a week or two. So although it can take up to 2 months before mineralisation is complete it is not usually necessary to wait anywhere near that long before adding fish. In this respect it probably helps to think of mineralisation and tank cycling as two separate but mutually inclusive processes.


----------



## darren636 (24 Sep 2012)

great post troi, as usual  i cycled my tank to 2 ppm ammonia. Most people cycle to 4 ppm. But my fish are tiny.


----------



## ceg4048 (24 Sep 2012)

Matt1988 said:
			
		

> I read somewhere someone said planted tanks aren't cycled the same way normal tanks are I was just wondering what the difference was


Hello,
   All tanks cycle in the same way. What we call the nitrification cycle is simply the buildup of populations of certain species of bacteria that we consider helpful, and which are those species that contribute to the oxidation of highly toxic Nitrogen compounds such as ammonia and Nitrite into the much less toxic Nitrogen compound Nitrate.

The problem with a new tank is that the population of bacteria required to safely oxidize these Nitrogen compounds number in the trillions. In one milliliter of water the required microbe count may be somewhere on the order of 50-100 million. The sediment and filter media population required is somewhere around 40-50 million per gram of sediment. These numbers are astounding and they are not achievable overnight.

Normally, bacteria reproduce by a process known as "binary fission", in which one bacterium splits into two bacteria. Each of the two split and become four bacteria, and so on and so on. It therefore takes many weeks to go from a population of one, to a population of one trillion.

So it's a numbers game. To have any appreciable effect on the concentration of toxic Nitrogen compounds, you need large numbers of the microbes.

In an unplanted tank, while the bacteria are busy building their populations, the only safe way to keep fish alive is to continually reduce the ammonia and nitrite concentration buildup is by continually removing water.

In a planted tank, the plants absorb and feed on the ammonia, so essentially, plants compete with the bacterial population for ammonia. But the plants must be healthy for that to happen effectively.

Many people assume that these bacteria only require ammonia, and that the more ammonia the better, but this is only half the story. The bacteria also require Oxygen, as well as K, PO4, and micronutrients. When people dump loads of ammonia in their tank, they think that they are helping the bacterial growth, but in fact they are killing the very same bacteria they are trying to cultivate.

In an unplanted tank there will be a severe shortage of Oxygen. This Oxygen limitation will limit the ability of the bacterial population to grow. It doesn't matter how much ammonia is dumped into the tank if there is insufficient Oxygen and insufficient PO4, K, carbohydrates and micronutrients. These are the limiting nutrients, not ammonia.

In a planted tank, assuming the plants are healthy, plants release massive amounts of Oxygen, not only into the water column, but they also transfer the Oxygen into the sediment because their roots require Oxygen supplementation after the roots are flooded. The Oxygen sent to the roots to keep them alive then escapes into the sediment so that the bacterial populations in the sediment are not limited by the poor Oxygen levels typical of unplanted sediments. Plants also release carbohydrates such as sugar into the water and sediment. So although the plants compete with the bacteria for ammonia, they actually help the bacteria by providing the starch and Oxygen the bacteria require to build healthy populations. Since Oxygen and nutrition is available, a wider variety of aerobic bacterial species can develop.

In a healthy, well planted thank therefore, the bacterial population rise more quickly and are sustained more easily because they have access to almost unlimited nutrient, carbohydrate and Oxygen levels. The so-called "cycle", which is the simple buildup of bacterial population, still occurs, but occurs more rapidly and with better stability. There is no need to add toxic ammonia to the tank. The organic matter in the tank from the plant leaves themselves which fall off, decay and provide the bacteria with the ammonia they require. Every surface of the plant is already covered with bacteria so the tank becomes seeded with these forms. One can add a little mulm from another tank or even a bit of garden soil to the sediment and filter to add more numbers. There is no need to buy bacteria because they are everywhere.

So these are the fundamental differences between an unplanted and a planted tank. So it is not that something "different" happens, it's simply that the things that happen, the things that we want to happen are massively enhanced by the presence of healthy plants. And that is why we are encouraged to start the tank with as many plants as possible, and with as many rooted plants as possible, because it is the substrate that does a lot of the heavy lifting in terms of bacterial population and nitrification.

Cheers,


----------



## Nathaniel Whiteside (24 Sep 2012)

Fantastic descriptive insight, great post.


----------



## dw1305 (24 Sep 2012)

H all,
Troi's is a good point about soil ,and he and Clive have really said it all. This subject comes up frequently, and often generates a lot of heated discussion, but it honestly is that simple. 

If you look through the "cycling threads" on most fish-keeping forums you will find that the discussion is all about ammonia (NH3) and whether various commercial products work, but very rarely does any-one ever mention oxygen (O2). If you read the technical literature on water pollution, aquaculture and waste water treatment, it concentrates on oxygen, and most importantly BOD - Biochemical Oxygen Demand. *For biological filtration to be successful, your oxygen supply needs to exceed the oxygen demand at all times. * Once you've fulfilled this criteria, all the other steps fall into place naturally. 

Personally  I think part of the problem is that many of the sellers of "bacteria-in-a-jar", cycle supplements etc don't want people to have stable successful aquaria, they want them to stagger from, real or imagined, crisis to crisis, all the time buying the next wonder product  or "instant quick fix". If you can first confuse them with a lot of pseudo-scientific half truth about "the cycle", leading to initial problems with fish death and algae, keeping them credulous becomes a lot easier. If you can convince people that plants are difficult to grow, and don't add any benefits, even better, because actively growing plants are the largest single factor that makes tank management easier.

Telling people that you don't need to buy anything but plants, and the only wonder product is the "passage of time", may be accurate but it doesn't do much for the balance sheet.

Have a look here for some more details: 
<http://www.ukaps.org/forum/viewtopic.php?f=21&t=20856>,
<http://www.ukaps.org/forum/viewtopic.php?f=21&t=10572>, 
<http://www.ukaps.org/forum/viewtopic.php?f=21&t=18200&hilit=fishless+cycling+Darrel&start=10> 
& http://www.ukaps.org/forum/viewtopic.php?f=9&t=17590&p=180865.

Also the ever informative "Skeptical Aquarist" has an interesting take on cycling <http://www.skepticalaquarist.com/fishless-cycling> & <http://www.skepticalaquarist.com/nitrogen-cycle>.

cheers Darrel


----------



## Matt1988 (24 Sep 2012)

Thanks for all the replies there a huge help 

 I was planing on using cat litter as a substrate would it be advisable to use this with soil and use the cat litter as a capping to hold onto the extra nutrients the soil would release?

Matt


Sent from my iPhone using Tapatalk


----------



## dw1305 (24 Sep 2012)

Hi all,


> I was planing on using cat litter as a substrate would it be advisable to use this with soil and use the cat litter as a capping to hold onto the extra nutrients the soil would release


It depends what you want from the tank really, if you aren't going to add CO2, but you want lush plant growth with a high biomass, a soil substrate is a good way to go as it potentially can supply a lot of nutrients and add CO2 as its organic carbon content is oxidised. 

The other factors you need to take into account are that light (PAR or "photosynthetically active radiation") drives photosynthesis, and photosynthesis drives nutrient uptake (including CO2). The whole process is like an assembly line, with plant growth restricted by which ever resource is limiting (PAR, CO2 or macro/micro-nutrient availability). Adding more of a non-limiting element doesn't increase plant growth, but it may prove harmful as some micro-nutrients are toxic at higher levels, the extra-energy from light may damage photo-systems, or high levels of one nutrient may block uptake of another nutrient. 

*Soil*
If you use soil this will have both humus and clays, which will add CEC (cation exchange capacity), as well as some amount of available nutrients, and a reserve of nutrients that will become available (via microbial action) over time. If you use soil you can cap it with sand, and you don't really need the cat litter. What you can't control is the initial nutrient release, as this will depend upon the soil you use, and these aren't easy things to measure. *A cat litter capping won't have much effect on the nutrient content of the tank water during mineralization.* 

I don't want an uncontrolled initial release of nutrients, or rapid plant growth, so I use a slightly different approach in that I use an inert sand media with a small amount (~5%) of added clay and humus.  

*Cat Litter* (or Akadama etc)
Cat litter is slightly different, in that it doesn't have any nutrients, available or in reserve. It is calcined moler clay, and even though it has been heated, it retains the CEC of its constituents clay. Because of this we have much more control over nutrient levels right from the start, the only nutrients we have are those we have added via EI dosing, or a basal dressing of osmocote etc.. The advantage it has over sand is that it does have a CEC, so can potentially hold and exchange nutrients. 

Again as I'm not interested in maximal plant growth, I use the "duckweed index" as a fertilisation method, there is a description of it here: <http://www.ukaps.org/forum/viewtopic.php?f=11&t=22824&hilit=+Duckweed+index>.

cheers Darrel


----------



## Tim Harrison (24 Sep 2012)

Matt1988 said:
			
		

> Thanks for all the replies there a huge help
> 
> I was planing on using cat litter as a substrate would it be advisable to use this with soil and use the cat litter as a capping to hold onto the extra nutrients the soil would release?
> 
> ...



In addition to Darrel's advice, from a practical point of view cat litter is very light and therefore is perhaps not the best material for capping a soil substrate as both will be easy to disturbed. 

I have however, used it instead of grit when making my own soil substrate in an attempt to take advantage of its potential benefits...not sure how worthwhile it was though.


----------



## Matt1988 (24 Sep 2012)

I like the colour mainly of the cat littler it's a bonus that its good for the plants with the right ferts  so if I had it

tank base> plant fert> cat litter > plants > water > filter

would I need to add anything to the mix to help the tank cycle or with time will it do it on its own? Oh I will have lights and co2 too  I'm planing on using 2x 24W T5's the tank will be close to 200L with around 10X circulation and if it needs it I have a 4x 24W T5 light unit I could add or swap with the first two T5's

Matt


Sent from my iPhone using Tapatalk


----------



## ceg4048 (24 Sep 2012)

Yes, add more plants and stop thinking about adding more light.

Cheers,


----------

