# Low Tech Fertiliser Dosing. Whats your technique?



## si walker (25 Apr 2022)

I get the feeling that us so called Low Techers beat to the sound of a different drum when it comes to dosing ferts.
Recently I have had a conversation with another group member about exactly this and I was really interested in what everyones approach was.
Personally I am loading my tank with ferts and not really sure if its necessary, being low tech and low light.
This leads me to doing weekly maintenance like its a high energy tank. I'm thinking of adopting a new approach and will keep you posted on how it goes.
Looking forward to hearing your ideas. 
Cheers.
Simon


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## Keys_Tanks (25 Apr 2022)

Hey! 

The key for this is floating plants as an indicator. I use tropica specialised for my 30lt low tech. 3 pumps per week sometimes 4 with medium lighting at most. 

When I first setup my tank I used floaters to gauge If was dosing enough. They indicate lack in nutrition very quick as they have access to co2. Once I found out how my low tech operates then I removed the floaters and had great success don’t get me wrong the odd bit of stag horn came but that got dialled out pretty easily due to having my lights just abit too bright cause originally I had floaters blocking abit of light out . 

Hope this helps 

Josh


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## Zeus. (25 Apr 2022)

Well @dw1305 adds ferts when his duckweed isn't so green, Via his duckweed index and does a WC when his TDS goes above a certain level, he calls it 'a low carbon foot print approach' or was it 'lazy approach' - I think its a  'smart approach'


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## The Miniaturist (25 Apr 2022)

Hi there,
I suppose it depends on the type of plants & how many.
If you're stuffed side to side, front to back & up to the waterline I imagine the plants' access to fertiliser will be more crucial & fert quantities will be greater than a tank of wafting stems with chunks of bogwood covered in moss.
Like @Keys_Tanks I use floaters to gauge whether I'm dosing sufficiently. I use premixed fertiliser but try to add macros & micros as I don't have many fish.


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## si walker (25 Apr 2022)

The Miniaturist said:


> I suppose it depends on the type of plants & how many.


Really good point. As you say the amount of fish you have comes into play.
I did try floating plants but I have a lid and they rot due to the constant drips of water.

Do you guys tend to also do less water changes than high energy tanks?


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## ElleDee (25 Apr 2022)

I have tanks that are fairly heavily stocked, very soft tap water, an active substrate, and a very high plant mass with both fast and slow growers. I dose K, Ca, Mg, and micros, but not N nor P. 

I used to have floating salvinia, but I found that once my tank matured they weren't contributing anything to the tank anymore. They were just taking light and nutrients away from the plants below, and throwing the extra away was a chore. Also, as my water column got leaner they weren't happy about it. They were useful in the setup period, but I am glad to not have to deal with them anymore.

I do a 50% weekly WC on my main tank and 25% on my shrimp tank. I enjoy tank maintenance though, so I am not trying to minimize it.


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## The Miniaturist (25 Apr 2022)

Both my tanks have covers, I don't have any issues with condensation but the covers are shaped so the condensation runs away without dripping.
I have a 57l and a 25l, water changes are one 8l bucket for the big tank & half a bucket for the small one every four days!
That's about 30% a week overall. Like @ElleDee I enjoy the maintenance as it's not too onerous.


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## KirstyF (25 Apr 2022)

I ran low techs, low light, before I even knew EI existed and things seemed to work pretty well with an All in One as directed on the bottle tbf! A little more now and then when things needed a boost, a little less when I forgot! Like people say, that actual amount will depend on plant choices and fish loads etc. 

Always still did a weekly water change, though at about 25%, and barely knew algae existed. Trimming and titivating was certainly a less frequent occupation. 

I’ve also always had lidded tanks and never suffered much from losing floaters. If you are able to crack the glass lids open just a smidge, the extra circulation can really cut down on dripping (beware jumpy fish and acrobatic Amano’s, a little bit of mesh can help with that, I’ve discovered!)

If ur dead set against floaters and want to dose ‘as needed’ rather than a set amount,  I wonder if anyone could suggest a good submerged ‘canary plant’ to incorporate? (If there is such a thing) It’s always good to have something that will shout at you before things go too far south!


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## Djoko Sauza (25 Apr 2022)

Zeus. said:


> Well @dw1305 adds ferts when his duckweed isn't so green,


Yes, I encourage all low tech folks to give the Duckweed Index a try, all you need is some floaters and complete fertilizer. Add in a cheap TDS meter and you have pretty much all the information you need about your plants needs.
It is like the opposite of EI, genius nonetheless. 



Zeus. said:


> and does a WC when his TDS goes above a certain level


I'm pretty sure @dw1305  does 10% daily water changes with mostly rain water, adding tap water to reach a certain conductivity value he found his plants grew at. Apparently he found his fish were healthier when they had more water changes. Correct me if I'm wrong 

Whichever way, I agree it is a smart approach!


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## MichaelJ (25 Apr 2022)

Zeus. said:


> Well @dw1305 adds ferts when his duckweed isn't so green, Via his duckweed index and does a WC when his TDS goes above a certain level, he calls it 'a low carbon foot print approach' or was it 'lazy approach' - I think its a 'smart approach'


Very smart indeed - and he doesn't use very much (citation needed)... and its very, very livestock friendly!... super low conductivity with rain water...  dare I call it _lean - without the drama _ 
I am more or less using my "duckweed" (actually Frogbit, Pennyworth and Duckweed) to gauge the plant health in one of my tanks., but I keep the dosing fairly consistent and relatively high for a low-tech in that tank.  The only minor concern,  is that the approach is somewhat reactive - i.e. the "damage" is somewhat already done when you start to see deficiency issues and it can be notoriously hard to identify what nutrient is actually missing.   But yes, it works!

Cheers,
Michael


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## Djoko Sauza (25 Apr 2022)

si walker said:


> I did try floating plants but I have a lid and they rot due to the constant drips of water.


You can try plants that do fine submerged and use them as floaters such as Brazilian Pennywort (Hydrocotyle Leucocephala) or Water Sprite (Ceratopteris thalictroides).


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## dw1305 (25 Apr 2022)

Hi all,


Djoko Sauza said:


> I'm pretty sure @dw1305 does 10% daily water changes with mostly rain water, adding tap water to reach a certain conductivity value he found his plants grew at. Apparently he found his fish were healthier when they had more water changes. Correct me if I'm wrong


Exactly that, I found a <"goldilocks zone"> where I had healthy fish and some plant growth. In some ways it is the path of least resistance, but <"I've scaled my peak">, it is just a pretty low altitude one.


MichaelJ said:


> The only minor concern, is that the approach is somewhat reactive - i.e. the "damage" is somewhat already done when you start to see deficiency issues and it can be notoriously hard to identify what nutrient is actually missing.


I'd agree that is a limitation, and also one that affects Amazon Frogbit (_Limnobium laevigatum_) more than Lesser Duckweed (_Lemna minor_).

By the time you see a visible deficiency of an immobile nutrient (one that effects new leaves), it is a while before the plant grows new healthy leaves, even when that nutrient becomes non-limiting.  I'm actually using a <"hybrid duckweed index"> at the moment, where I add iron (Fe) and magnesium (Mg) on a regular basis.

The advantage that _Lemna minor _has, is that it has a very quick turn over of fronds, so new green leaves appear within a day or two. With  _Limnobium laevigatum _it <"takes longer for new healthy leaves to grow">.

cheers Darrel


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## MichaelJ (26 Apr 2022)

dw1305 said:


> Hi all,
> 
> Exactly that, I found a <"goldilocks zone"> where I had healthy fish and some plant growth. In some ways it is the path of least resistance, but <"I've scaled my peak">, it is just a pretty low altitude one.
> 
> ...


Hi Darrel, I might not be the only one being curious about what you are dosing so I thought I would ask.  Do you target any specific ppm's with your fertilizers? what's your technique? 

Cheers,
Michael


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## Wookii (26 Apr 2022)

MichaelJ said:


> Do you target any specific ppm's with your fertilizers? what's your technique?



Without wishing to speak for him, I believe Darrel uses the 'pinch or dip' technique with dry salts using complex mammalian opposable digits - not a gram scale in sight!


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## tam (26 Apr 2022)

I think rotala could work as a rough under water indicator in low tech, if you look at a long stem you can see the leaf size and stem change when ferts have got a bit lean and then recovered again. I haven't paid attention to how rapid the reaction is though.


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## Tim Harrison (26 Apr 2022)

Darrel’s Duck Weed Index








						The scientific background to the  "Leaf Colour Chart"
					

Hi all, As a couple of people have asked about the ), I'll add some references into this thread, I'll add more as I collect them.    The LCC was developed to give  a visual indication of the nitrogen status of their crop. The University of California, in collaboration with the California Rice...



					www.ukaps.org
				




Or take a look at this








						Non CO2 methods
					

While much of the attention and aquascape seen on the web focuses on CO2 enrichment in their methods, Diana Walstad presents an excellent argument for the approach of a non CO2 enriched planted Aquarium. We should also extend this to include Excel and carbon enrichment liquids as well as acetate...




					barrreport.com


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## dw1305 (26 Apr 2022)

Hi all,


MichaelJ said:


> I might not be the only one being curious about what you are dosing so I thought I would ask. Do you target any specific ppm's with your fertilizers? what's your technique?


I don't target any particular nutrient levels, but now we have <"some analytical kit that will simplify the whole process"> of nutrient testing I will run some tank water samples through the AES when / if I have time.

At the moment my fertiliser regime is <"pretty _ad hoc._"> for both magnesium (Mg) and iron (Fe), and consists of a small slosh of <"very pale  blue  Miracle-Gro"> (when I think the tank needs it, based on the <"Duckweed Index">) for everything else. 

When I run out of "Miracle Gro" I've bought a kilo of <"Solufeed 2 : 1 : 4 mix">. When I start with the <"Solufeed"> I'll work out what gives me 10 ppm nitrogen (N) (and ~44.3 ppm NO3 equivalent) and dilute that <"in  a milk carton (6 pints of water)"> to see how blue that looks. Then I just need to ensure that the water I add to the tank is always less blue than my trial run.

Also I haven't tested conductivity recently, I've just observed <"the snail shells">.

cheers Darrel


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## dw1305 (26 Apr 2022)

Hi all,


dw1305 said:


> When I run out of "Miracle Gro" I've bought a kilo of <"Solufeed 2 : 1 : 4 mix">. When I start with the <"Solufeed"> I'll work out what gives me 10 ppm nitrogen (N) (and ~44.3 ppm NO3 equivalent) and dilute that <"in a milk carton (6 pints of water)"> to see how blue that looks. Then I just need to ensure that the water I add to the tank is always less blue than my trial run.


I should probably put in the calculation for that.

The tank is a nominal *70* litres and
I want *10 ppm N*
Solufeed 2 : 1 : 4 is *15% nitrogen* (N).
There are 1000 mg in a gram, so 1 gram of Solufeed contains *0.15g or 150 mg N, "mg / L" and "ppm" are equivalents.*
150 / 70 = *2.14 ppm N in 70 litres*
10 / 2.14  = *4.667. I need to add 4.67*g Solufeed 2 : 1: 4 to give *10 ppm N in 70 litres of water, *and then to check
Check = 4.667 * 150 = 700, 700 mg is the total mg N added and 700 / 70 = 10 mg  / L (ppm).
cheers Darrel


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## dw1305 (26 Apr 2022)

Hi all,


Wookii said:


> I believe Darrel uses the 'pinch or dip' technique with dry salts using complex mammalian opposable digits - not a gram scale in sight!


Speak away, I do, and <"it really isn't good enough">, but in my defence I'm used to working with chemicals, so I have a fairly good idea of what 10g of a salt looks like and of which salts are denser. If I'm not sure? I will get the scales out.


tam said:


> I think rotala could work as a rough under water indicator in low tech,


It was a floating plant, just because it took CO2 out of the equation. There has been a suggestion, on this forum, that all plant growth issues are CO2 related. Purely in terms of the mineral nutrition? Any green fast growing plant will do.

cheers Darrel


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## Kelvin12 (26 Apr 2022)

This is the best forum ever.  You could spend days here reading there is just so much to digest.  I have so many bookmarked posts the list now runs into pages.   I think I need a computer just dedicated to these articles. 

Dirk


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## MichaelJ (27 Apr 2022)

Wookii said:


> Without wishing to speak for him, I believe Darrel uses the 'pinch or dip' technique with dry salts



This is hilarious...well @Wookii,  lets see what Darrel says here:



dw1305 said:


> At the moment my fertiliser regime is <"pretty _ad hoc._"> for both magnesium (Mg) and iron (Fe), and consists of a small slosh of <"very pale  blue  Miracle-Gro">



_A small slosh ..._ I love this  A _slosh_ is similar to a _slop_ which is close to a _splash_ which is widely recognized to be just about 5.91 ml. I suppose a small slosh would be around 3 ml...  - hard to say if thats a lot for a 70 L low-tech tank, but we do not have enough information to work out the ppm's.



dw1305 said:


> When I run out of "Miracle Gro" I've bought a kilo of <"Solufeed 2 : 1 : 4 mix">. When I start with the <"Solufeed"> I'll work out what gives me 10 ppm nitrogen (N) (and ~44.3 ppm NO3 equivalent)


Now, 10 ppm of N, that was worked out fairly painstakingly...  Again,  a lot for a low-tech! I am curious about the rationale for that high level of Nitrogen, but I suppose that the _occasional_ dosing will have to make up for a pretty long run.



dw1305 said:


> and dilute that <"in  a milk carton (6 pints of water)"> to see how blue that looks.


So  the blue color comes from a dye that is used in  terrestrial fertilizers to enable the user (applicator)  to see what has and hasn't been fertilized and how even the distribution is. It can also be used to gauge the concentration of the fertilizer when diluted into a liquid - see below:



dw1305 said:


> Then I just need to ensure that the water I add to the tank is always less blue than my trial run.


Sounds pretty slipshod, but in reality its probably  accurate enough if your memory for color is good  



dw1305 said:


> Also I haven't tested conductivity recently, I've just observed <"the snail shells">.


An here comes... wait for it... The Snail Shell index...!





Wookii said:


> Without wishing to speak for him, I believe Darrel uses the 'pinch or dip' technique with dry salts using complex mammalian opposable digits - not a gram scale in sight!


Perhaps the message here is that we  too often waste our time getting too caught up in measuring things out to the last digit on our microgram scales?  

Cheers,
Michael



Kelvin12 said:


> This is the best forum ever.  You could spend days here reading there is just so much to digest.  I have so many bookmarked posts the list now runs into pages.   I think I need a computer just dedicated to these articles.
> 
> Dirk


I very much agree...  What sets UKAPS apart is the excellent _signal to noise ratio..._  While other forums may have a lot more members, and thus posts, you will have to dig through _a lot_ more less relevant posts (_noise)_ to find the good information_ (signal)._

Cheers,
Michael


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## dw1305 (27 Apr 2022)

Hi all, 


MichaelJ said:


> Now, 10 ppm of N, that was worked out fairly painstakingly... Again, a lot for a low-tech! I am curious about the rationale for that high level of Nitrogen, but I suppose that the _occasional_ dosing will have to make up for a pretty long run.


I don't pour in the whole six pints, just an amount (again unspecified) and it is occasional dosing. 

For the home tanks on Saturday morning,  when I'm watering / feeding the house plants (and containerised Blueberries, Azaleas etc) I'll look a the tanks, if the Frogbit looks a bit pale the tank gets a slosh of fertiliser, if it looks hale and hearty? It doesn't.


MichaelJ said:


> Perhaps the message here is that we too often waste our time getting too caught up in measuring things out to the last digit on our microgram scales?


Agreed, but it is slightly different for me. I've kept tanks for a long time, I have no interest in optimal growth (or aesthetics or "rare" plants) and plants have been both my day job (and my amateur interest) since I was in my teens.

cheers Darrel


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## kayjo (27 Apr 2022)

What does the "Duckweed index" indicate when the floating plans are thriving, but all the submerged plants still are unhealthy and dying?


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## si walker (27 Apr 2022)

Wow. This has been my best post so far!
I new that there would be many hidden tips that people do daily and others can learn from. The idea of reading the plants, duckweed or stems is really fascinating.
Keeping a LT tank in a LTech way is whats interesting. 
I now need to start looking into those other plants that can be used as floaters and also TDS Meter.
AMAZING replies.
Keep em coming if its helpful.
Thanks all.
Simon


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## MichaelJ (27 Apr 2022)

dw1305 said:


> I don't pour in the whole six pints, just an amount (again unspecified) and it is occasional dosing.


Yes, I got that part wrong. Sorry.



kayjo said:


> What does the "Duckweed index" indicate when the floating plans are thriving, but all the submerged plants still are unhealthy and dying?


Hi @kayjo,  I have not experienced this myself, but in my case I used it only in low-tech tanks with _easy plants_.  I suppose it  depends on what type of plants we are talking about, and if this a low- or high tech tank, what the state your tank is in etc.. If this is a current problem in your tank, I suggest you post the issue in the Plant Help section and post some pictures with additional tank details, so we can see what the situation is.

Cheers,
Michael


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## John q (27 Apr 2022)

kayjo said:


> What does the "Duckweed index" indicate when the floating plans are thriving, but all the submerged plants still are unhealthy and dying?


For me it would indicate that the issues aren't nutrient related, at least not lack of nutrients. 
I used this method when reducing my dosing and when a noticed issues with the frogbit I knew I'd reduced the fertiliser to much.

Frogbits a good canary for "nutrient" deduction, it isn't starved of C02, so that can be ruled out, and it gets first dibs of any light, again taking lack of light out of the equation.


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## The Miniaturist (27 Apr 2022)

It could be the nutrients are borderline sufficient so the frogbit, having access to plenty of CO2, is using most of them & starving the plants beneath it. Also shading them too much if the light is low.

As @MichaelJ said, put the question in Plant Help & you'll get a load of help.


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## Tim Harrison (27 Apr 2022)

The Miniaturist said:


> It could be the nutrients are borderline sufficient so the frogbit, having access to plenty of CO2, is using most of them & starving the plants beneath it. Also shading them too much if the light is low.


I don’t think it works that way. Having access to atmospheric CO2 means floating plants react quicker to changing nutrient status. Thus observing leaf colour and dosing when appropriate means any potential deficiency is avoided before it becomes an issue for submersed plants


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## MichaelJ (27 Apr 2022)

Tim Harrison said:


> I don’t think it works that way. Having access to atmospheric CO2 means floating plants react quicker to changing nutrient status. Thus any potential deficiency is avoided before it becomes an issue for submersed plants



Hi Tim, Generally I would say it works, but I am torn on the _corner-cases_. I could see the floaters being unlimited on CO2/light, as they are, potentially could be starving off the plants underneath if the tank is tethering on nutrient deficiencies. Some reports that Frogbit are quite greedy when it comes to Nitrogen especially - so if you have a lot of floating plants that could be an issue. Again, I think the type of submerged plants have to be factored in as well. You might think you are adding enough nutrients, but the submerged plants might have a hard time with uptake due to other water parameters / conditions. 

Cheers,
Michael


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## Tim Harrison (27 Apr 2022)

It’s an indicator and it works very well when applied with common sense.


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## dw1305 (27 Apr 2022)

Hi all,


kayjo said:


> What does the "Duckweed index" indicate when the floating plans are thriving, but all the submerged plants still are unhealthy and dying?


What @John q says, either lack of light or lack of CO2.

cheers Darrel


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## jaypeecee (27 Apr 2022)

Hi @dw1305

Having never used the Duckweed Index to any meaningful extent, what are the implications for submersed plants as regards lighting intensity? Floating plants will obviously receive more light than submersed plants and floating plants receive the same spectrum as that being emitted by the light(s). But, underwater plants will see things differently. Or, am I missing a trick?

JPC


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## dw1305 (27 Apr 2022)

Hi all, 


jaypeecee said:


> Floating plants will obviously receive more light than submersed plants and floating plants receive the same spectrum as that being emitted by the light(s). But, underwater plants will see things differently. Or, am I missing a trick?


I assume it is just a PAR effect. The bottoms of all my tanks are pretty gloomy, and just tend to have Aroids, ferns and mosses.

cheers Darrel


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## _Maq_ (3 Jul 2022)

kayjo said:


> What does the "Duckweed index" indicate when the floating plans are thriving, but all the submerged plants still are unhealthy and dying?





dw1305 said:


> either lack of light or lack of CO2.


1. lack of light - yes
2. lack of CO2 - no
3. lack of oxygen
4. elevated dissolved organic compounds in the water column
5. high oxygen demand in the substrate, i.e. too much easily degradable particulate organics in the substrate.
I oxygenate water permanently, so I keep CO2 always low but not missing altogether. Growth is much slower compared to CO2 enhanced tanks, but I don't believe any true submerged plant suffers from low (i.e. _normal_, in fact) level of CO2.
There are always *growth supporting* and *killing* factors at play simultaneously. CO2 injection is growth supporting, so it helps plants to overcome other, killing factors' effects. I prefer the other way - eliminating the killing factors (see above the list). Normal level of CO2 seems to be no problem.


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## Wookii (3 Jul 2022)

_Maq_ said:


> 2. lack of CO2 - no



Of course it can indicate a lack of CO2? We’re not talking a high tech CO2 injected tank here, we’re talking a low tech one. 

A low tech tank requires good surface agitation to optimise gas exchange both of O2 and CO2 - both come hand in hand. 

It’s very easy for areas of a low tech tank to be devoid of dissolved CO2 unless that water is regularly replaced with water from the surface which is at equilibrium with atmospheric levels of CO2, simply because levels are so low to start with. You are doing exactly that here:



_Maq_ said:


> I oxygenate water permanently, so I keep CO2 always low but not missing altogether.



You are not keeping CO2 low by doing that (in the context of a low tech tank), you are keeping CO2 as high as it can be in a low tech tank, by ensuring that CO2 loaded water at the surface is mixed with the rest of the tank.


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## _Maq_ (3 Jul 2022)

Wookii said:


> you are keeping CO2 as high as it can be in a low tech tank, by ensuring that CO2 loaded water at the surface is mixed with the rest of the tank.


Am I? Apart from the plants, tanks are usually net CO2 *producers*.


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## Wookii (3 Jul 2022)

_Maq_ said:


> Am I? Apart from the plants, tanks are usually net CO2 *producers*.



True, but not nearly at the rates that plants consume it, and no way near as much as can be introduced by good surface gas exchange.


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## dw1305 (3 Jul 2022)

Hi  all,





_Maq_ said:


> Am I? Apart from the plants, tanks are usually net CO2 *producers*.


I think the point is that you can' t take plants out of the equation, they are massively both net oxygen producers and CO2 consumers.

Cheers Darrel


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## _Maq_ (3 Jul 2022)

dw1305 said:


> Hi  all,
> I think the point is that you can' t take plants out of the equation


They are CO2 consumers, during daylight. So, the question is, whether fish and microbes provide them more CO2 than oxygenation? @Wookii took for granted that oxygenation makes the water saturated with CO2 as much as possible. While I believe that this is not the case, except in the afternoon, perhaps.
In other words, if I didn't oxygenate, CO2 level would be higher than 0.5 ppm during night and earlier half of the day.


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## John q (3 Jul 2022)

_Maq_ said:


> In other words, if I didn't oxygenate, CO2 level would be higher than 0.5 ppm during night and earlier half of the day.


@_Maq_  you seem like an educated guy, other than being argumentative and splitting hairs, perhaps you could show us the fruits of your labour's. 

I for one think I can attain some knowledge from you, but you need to show us your onions 😀


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## dw1305 (3 Jul 2022)

Hi all,


_Maq_ said:


> So, the question is, whether fish and microbes provide them more CO2 than oxygenation? @Wookii took for granted that oxygenation makes the water saturated with CO2 as much as possible. While I believe that this is not the case, except in the afternoon, perhaps.


I don't understand where this going.

*Plants are net CO2 consumers*, it isn't a suggestion or a hypothesis. The <"oxygen we breathe">, <"fossil fuels we burn"> and <"the steel we use"> were entirely created from the difference between the CO2 consumed and oxygen evolved during photosynthesis.

@Geoffrey Rea <"measured dissolved oxygen  over a 24 hour period"> in his high tech tank, with some surprising findings.

I don't think any-one is arguing that <"dissolved oxygen isn't important">, I'm certainly not, in fact quite the opposite.


dw1305 said:


> The reason for all this is that the prime metric we are interested in is dissolved oxygen, and nearly everything else is just "froth". We want the biological filtration media to be fully oxygenated (for the oxygen supply to exceed the oxygen demand). In the case of a planted tank, with your filter, it is going to be quite difficult to arrive at a situation where you have de-oxygenated media.


We have a thread <"maximising dissolved O2"> and another on <"maximising CO2 in a low tech tank">.

Personally I like some <"laminar flow"> (and <"direct aeration">) to replenish the <"levels of dissolved gases">. As  general rule as the bioload get larger the gas exchange surface area <"also needs to gets larger">, this is to both outgas CO2 and replenish dissolved oxygen.

If we measure the <"diel variations in pH"> it gives you a pretty good indication of the CO2:O2 balance.

cheers Darrel


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## _Maq_ (3 Jul 2022)

John q said:


> @_Maq_  you seem like an educated guy, other than being argumentative and splitting hairs, perhaps you could show us the fruits of your labour's.
> 
> I for one think I can attain some knowledge from you, but you need to show us your onions 😀


Okay. I'll make my introduction. Give me a few days.


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