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Cycling a heavily planted tank

Thank you everyone for replying my question about testing. Sorry for my late reply. I've read all the info from the links and bought some Tropica Salvinia Auriculata as the shop didn't have any Amazon Frogbit. I was away for 5 days and the plants just flourished without me fussing and tweaking things all the time! We've now added 7 Green Tetras and 7 Cardinal Tetras to join the existing 7 Neocaridina blue dream shrimps. I'm a bit nervous about not doing a test now that I've increased the bio load. Could you please tell me what are the things I should do or look for now that I've added the fishes (without testing)? Thanks again.
 
I'm a foreigner, so pardon me for learning English this way...
What is the meaning of the word CYCLING? Is it
(a) the period after establishing the tank when the microbial community is not yet developed, or
(b) active measures (adding ammonia etc.) we take to achieve that goal?
 
I'm a foreigner, so pardon me for learning English this way...
What is the meaning of the word CYCLING? Is it
(a) the period after establishing the tank when the microbial community is not yet developed, or
(b) active measures (adding ammonia etc.) we take to achieve that goal?
Cycling is a generic term for the nitrogen cycle in general terms. So basically your tank is cycled once ammonia and nitrite read 0. I purposefully omitted nitrate.
How you cycle the tank is a different debate.
 
... basically your tank is cycled once ammonia and nitrite read 0.
So it seems to be the same as in my country - all attention is devoted to nitrogen and other substances and microbial processes are ignored, right?
Then, how I am to call gradual development of the microbial community as a whole (of which nitrifiers constitute usually less than 1-2 per cent)?
 
So it seems to be the same as in my country - all attention is devoted to nitrogen and other substances and microbial processes are ignored, right?
Then, how I am to call gradual development of the microbial community as a whole (of which nitrifiers constitute usually less than 1-2 per cent)?
I think you are confusing two concepts. The nitrogen cycle, or as we call it "cycling a tank" is merely making sure that you don't have ammonia and nitrite. That's about it and I think that's pretty much universal. However, a cycled tank doesn't mean it is mature in any way, and it can take several months for a tank to reach a good level of maturity. Some will even claim years. This said, it doesn't mean you can't add fish once the cycle is just finished and the tank is still immature. You still need to be careful and go progressively. We usually refer to the nitrogen cycle in reference to living creatures (fish, shrimps etc) in general as it can be deadly to them. The term maturity is more for the overall state of the tank. Some shrimp breeders/owners will even claim that cycling alone the tank is not enough and it needs a certain level of maturity to receive inhabitants.
 
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Hi all,
What is the meaning of the word CYCLING? Is it
(b) active measures (adding ammonia etc.) we take to achieve that goal?
Cycling just usually refers to a binary divide between "not cycled" and "not fish safe" and "cycled" and "fish safe". Have a look at <"Dr Timothy Hovanec's comments about Bacterial supplements">.
(a) the period after establishing the tank when the microbial community is not yet developed,
Personally <"cycling isn't"> a term, <"or a concept">, I'm very happy with. I'm much keener on the idea of <"Seasoned Tank Time">, which takes a more holistic approach.

cheers Darrel
 
Some shrimp breeders/owners will even claim that cycling alone the tank is not enough and it needs a certain level of maturity to receive inhabitants.
I'm a plant keeper and I say the same: Plants should not be introduced before six to eight weeks, and fish & shrimps even later. Because, ammonia & nitrite ore only two among many harmful substances which appear when the microbial community is not yet developed and stabilized.
Of course, it is actually a matter of many months, and we can argue that it's a never ending process. That's true. But six weeks work for me just fine. I've lowered the loses substantially.
 
I'm a plant keeper and I say the same: Plants should not be introduced before six to eight weeks,
Well that is arguable in my opinion. As much as adding animals in an uncycled tank can be deadly to them, it is hardly the case for plants in an uncycled or immature tank. Obviously if you have a soil releasing lots of ammonia, it can be toxic to plants and certain very specific species will melt to the core, but decades and decades of people having planted tanks have shown that you can plant from day one without catastrophic issues for the plants. In fact it is part of making the tank mature faster so I don't see why one would need to wait 6 or 8 weeks to introduce plants. Obviously there is nothing wrong with doing that but to me that's totally unnecessary and does not provide any outstanding benefits.
 
@Hanuman, let me develop my arguments a bit further.
Obviously if you have a soil releasing lots of ammonia, it can be toxic to plants and certain very specific species will melt to the core, but decades and decades of people having planted tanks have shown ...
The crucial point here is that ammonia & nitrite are only minor part of the matter. An ideally 'matured' tank means that microbial community is complete and stable. That means that whenever a chemically unstable substance appears it is immediately transformed into another, a stable one. Unstable means in biochemistry quite the same as reactive, aggressive, harmful, poisonous. Also, 'an energy source'.
Take ammonia and nitrite as examples. Both can be easily oxidized with a net gain of energy. Yet we have to wait for specific microbes to arrive and propagate. Similarly, if decomposition of organic matter is incomplete, many unstable substances remain waiting for particular microbes to decompose them further. We cannot measure it as easily as ammonia and nitrite, so we ignore them. (The only cumulative measurement of this is biological and chemical oxygen demand, BOD, COD.) But they are no less harmful, namely to the plants. And high oxygen demand can lead to low oxygen level, as well, which too is dangerous for plants.
Naturally, I'm well aware that the common practice is different and largely successful. Easy going and rapidly growing stem plants, right? But I'm speaking about more demanding plants, and I don't inject CO2. I seek challenge. Easy plants are no challenge to me. As such, I've found this extra patience - six to eight weeks without plants - as clearly rewarding, decreasing my losses in newly established tanks.

One more note. It is generally believed that plants are beneficial for maturing the tank. Well, yes, they can uptake ammonia and nitrite. But, as a rule, they do not uptake partially decomposed organic matter. In fact, it is harmful to them, and they cannot take part in decomposition.
Plants can be beneficial to microbes by creating oxidized rhizosphere, that's true. But my experience tells me that it's better to wait till the microbes develop, and only then improve the state of affairs a bit with rooting plants.
 
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Hi all,
Well, yes, they can uptake ammonia and nitrite. But, as a rule, they do not uptake partially decomposed organic matter. In fact, it is harmful to them, and they cannot take part in decomposition.
Plants can be beneficial to microbes by creating oxidized rhizosphere, that's true. But my experience tells me that it's better to wait till the microbes develop, and only then improve the state of affairs a bit with rooting plants.
I think that the uptake of fixed nitrogen and supply of oxygen (to both substrate and water column) must outweigh any disadvantages in adding plants before the microbial assemblage is fully mature.

I always add a floating plant right from the start, and I honestly can't see any negative side to this.

cheers Darrel
 
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I always add a floating plant right from the start, and I honestly can't see any negative side to this.
If you mean plants like Limnobium, with floating leaves, they uptake ammonia in large amount but they don't oxidize the water. They exchange all gases at the upper side of their leaves. But they may exude organic substances through their roots which possibly serve as a colonization area for heterotrophic bacteria.
 
Hi all,
If you mean plants like Limnobium, with floating leaves, they uptake ammonia in large amount but they don't oxidize the water. They exchange all gases at the upper side of their leaves.
Yes that is right, all the stomata are on the upper surface.

<"This is a Potamogeton sp."> but Limnobium (or any other plant with floating leaves) would look similar. You can see the distribution of the stomata in the leaf cross section and they are all in the upper (adaxial) leaf surface.

It is actually the <"aerial advantage">, the <"access to atmospheric gases">, that makes floating plants so effective at reducing fixed nitrogen levels and also why you can add them <"to an immature tank">.

Their photosynthetic surfaces have access to 20% oxygen and 420 ppm CO2 and can't be choked by algae.

cheers Darrel
 
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Hi all,
And I still stick to my opinion that plants can hardly help maturing the tank. In short - microbes first, plants next.
I just think it is always going to be a <"synergistic process">, "plant / microbe" nitrification. I think there is also the effect of the <"ammonia loading on the microbial assemblage">. Personally I'm always going try and avoid the <"Mbuna scenario">.
I don't add much weight to allelopathy.
I've got <"my doubts as well">. I've altered my position a little bit since 2014 and I think <"it probably does occur">, but I've no idea how important it is.
......... Even if strict allelopathy (I'm also agnostic as to how important it might be) doesn't exist in terms of plants producing antimicrobial chemicals, it certainly <"exists in the rhizosphere"> where plants are actively altering the microbial assemblage to gain nutrients and using these microbial cohorts as soldiers in proxy wars with other plants.

It isn't surprising that <"antibiotics were isolated from soil bacteria">, cyanobacteria, actinomycetes, "fungi" etc have been waging biological war on each other for billions of years. That is partially why I'm agnostic about strict allelopathy.......

cheers Darrel
 
Hi all,
If you mean plants like Limnobium, with floating leaves, they uptake ammonia in large amount but they don't oxidize the water. They exchange all gases at the upper side of their leaves. But they may exude organic substances through their roots
A bit late as a reply, but I may have a been too hasty in only looking at <"gas exchange via stomata">.

I was reading a scientific paper today (it isn't a great paper), but they measured <"Radial Oxygen Loss (ROL)"> from the roots of "Water Lettuce" (Pistia stratiotes).

Rehman, F. et al. , (2023) "Optimal root oxygen release from two macrophytes Saururus cernuus L. and Pistia stratiotes L. varies with light and temperature in simulated constructed wetlands microcosms", Rhizosphere, 26, <"https://www.sciencedirect.com/science/article/pii/S2452219823000368">.
..... Maximum root oxygen release was at peak photosynthesis, thus correlated with light intensity. The temperature had an effect on stomatal conductance, photosynthesis rate, and transpiration rate was affected by the wind speed. For the highest stomatal conductance and photosynthesis, P. stratiotes required a higher temperature than S. cernuus. Stomatal conductance also influenced the oxygen released from plant roots. Furthermore, a relationship was determined between physiological processes and their potential to release oxygen from the roots where the reduction in COD and BOD measured at the end of the experiment was largely attributed to the oxygen that the macrophytes added .......
In Amazon Frogbit (Limnobium (Hydrocharis) laevigatum) there would be less oxygen release, just because of <"its low potential growth rate"> than P. stratiotes, but I'd guess it wouldn't be that dissimilar in scale.

I've just found that Diana Walstad actually talks about this, and has some pictures, in <"Small Planted Tanks for Pet Shrimp (2023)"> pdf - <"https://dianawalstad.com/wp-content/uploads/2023/05/potted-plants-2023.pdf">.
Walstad_ROL_Limnobium.png

cheers Darrel
 
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