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Method of controlled imbalances discussion

208076 Views 477 Replies 76 Participants Last post by  Eyeslikepeanuts
Well, GDA is easy to eliminate.
It's appears when there is an imbalance related to Po4 and Ca.
If Ca is high this is because you probably had added too much. 50% water change solves it. And reduced the quantity next time.
About Po4, Water change helps if the new watter hasn't Po4. Reducing the ppms you add helps a lot. I think that 0.5 is enough unless you have a lot of microsorums, marsilea crenata, etc.
This two items should be in your mind in order to avoid a new GDA problem.
Finally, to eliminate it you should use the "generic protocol of the Kno3". Stop fertilizing at all. Change 50% of the water. Add every day for 1 week 1 gram of Kno3 every 50 gallons until GSA appears. If after one week the GPA doesn't appears, then repeat it but 2 gram every 50 gallons and so on.
I know that in this forum you guys have very different ideas about how to deal with GDA. This way to solve it was sucesfully used hundred of times during the last three years.
You can find more info about this in this thread / article:
You know, when a theory doesn't work, then this theory should be abandoned.

Edit note: For full English translation, please refer to here, starting on post number 214.
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Re: Maracyn/gda experiment...

How do I translate this article? My high school Spanish isn't good enough, and I don't know how to use google translator. Thanks.
You go to, click on languaje tools. Then you copy paste the paragraph and select from spanish to english.
If you understand some spanish better because the technology is not good enough yet.
I suggest you start reading the chapter "el metodo de los desequilibrios controlados", because the beginning is an explanation about myths and how to tune up properly the aquarium,
Re: Maracyn/gda experiment...

Well, the main idea behind the MDC is to reach the GSA for three reasons. 1) close to GSA no other algae can bloom 2) the amount of Kno3 your aquarium needs to reach the gsa is the real consumption of your aquarium per week. That's the amount you should use for fertilizing. 3) If you have any algae, if you look for gsa, the algae stop bloom or die.
Fertilizing in this way makes that is you test your water there is never more than 2.5 ppm of No3.
In my opinion, rigid rules like 10.1.15 makes no sense, diferents aquariums have diferents balances: 20.1.15, 5.5.15, or whatever.

The idea about to work only about Kno3 is because if you work with too many other variables, then you don't know how to induce a solution. And if you solve it, you don't know why it happend.

In the other hand, the idea is to use your plants as the filter of your aquarium.

The MDC is only a frame, as soon as you understand it you can use any fertilizing method you want without algae. At the forum of many people use PPS or EI, etc.

In this thread you can read a little more (in english) about the MDC, this is an unfinished debate with Tom Barr (plantBrain):
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Re: Maracyn/gda experiment...

I read it and have a few questions about it that may be translation issues more than anything. Just cant do it right now.
Oki, as soon as you have some time I'll answer them.
Re: Maracyn/gda experiment...

I do realize you want use to dose KNO3 to a point a which green spot algae is the only one left. Is this correct? What then?
The main idea is that when you reach the GSA other algae die or stop bloom. If you see, there are several pictures with the most common algae, there are specific protocols to deal with them with the "generic Kno3 protocol" we are talking about.

In the beginning of your article you say "....seen throughout this work does not recommend the use of potassium sulphate....". However, a few pages in to the article you say "With regard to potassium, all indicate that this has an important role in halting the progression of sevral types of algae". and " could argue in principle that the use of potassium in the one of the key variables, or to avoid an explosion of algae or to control them. Potassium is an alkali earth metal and this could be why EI dosing works (for most) as there is so much K2SO4 that the algae cant survive as little is consumed by the plants and a 50% water change will not flush out enough to prevent the levels from continuing to rise over time.?
In this thread I debate with Barr about it:
When I mention potassium I don't mean potassium sulphate. You know, salts always have a partner: sulfate, chloridre, etc. I think that the best is to add two good ones instead of sulfate. Some friend from Chile use potasa 15-0-15 and works great!!
It's not a matter of high dosis, I believe that using the Kno3 protocol you can reach the real consumption of your aquarium and avoid algae bloom and have exccelente plant growth rate.

I really want to try your suggestions but it would be helpful to have a better guide, or is it as simple as dosing KNO3 at 1 gram per 200 liters three events per week. This equates only ~3 ppm per event.
This is a missunderstanding. The main idea behing the MDC is that rules like 10.1.15 doens't work. So I propose to use the generic protocol of Kno3 to induce gsa (algae control) and like a way to find the real consumption of your aquarium (fertilizing). You can read a lot about it in the debate with Barr. I suggest this very low doze like a start point (I really believe about to make everything simple for begginers). The idea is that all aquariums have different consumptions and differents balances. For example, if you have a carpet of marsilea crenata you will need to add a lot of Po4 in order to avoid gsa. If your carpet is a glosso one, then your aquarium will need a lot of Kno3 But, when you know exactly the consumption, then, plant are properly fertilized and if you test your water the No3 should be under 5 ppm.

Lastly, when talking about the amount of light per liter are you simply taking the given tank size or the volume of water actually subjected to the light. For instance, I have a 75 gallon tank BUT this is when measured on the outside. Once it has substrate and decorations in it the actual water is about 60 gals that has light on it. Several gallons are in the substrate and do not recieve light and the glass is 1/2 inch thick, etc.
I think that the approach about light should be understandable even for begginers. Usually it became too complex. The watt/liter rule is simple to understand and there is a convention about to use the raw litters or gallons.
My idea behind this is to use the plants as the aquarium filter, but I need at least 4 watts/gallon to have the plants filtering the aquarium properly. Esencially I have in mind plants like glosso, marsilea crenata, etc, I mean, the plants you are going to use to make a carpet.
Diana Wastald had a huge influence some years ago at spanish speaking forums and we had to work a lot to convice people to use some more light.

- Coadyudantes:
Somethin secundary, not important, that has a relationship with the principal thing but not important. I talk about when you have red algae and people says thay the cause is too long light period or that the filter is too strong, etc.

- Tapizantes:
Are the plants that makes a carpet, like glosso, HC, eleocharis, etc.

- Acuarismo ( I think it means the aquarium hobby)

- Sales (this seemed to be used in a couple/few different ways)
Means salt but I use to describe any fertilizer without chelate. There I criticize a group of argentina who prepared at home micros fertilazers without chelate but I don't mention them because is unpolite.

- GAP - green algae point o.r what you mean by point
mmmmm, should be GSA, green spot algae.

- Siguientres
It is a typing mistake, is "siguientes" and means "followings"

Please notice that the article continues below after Dorje comments. The MDC began as a debate and grew a lot from the feedback but we kept it as a thread, for this reason you will finde that there are some people answers in between.
The MDC finishes with this footnote:
"7. Sorín, Raúl, Tomo I, Instalación y Mantenimiento de acuarios, 1986, ed. Albatros, Bs. As. Argentina, p. 125 y ss."

You can have some more explaining info about the MDC in this interview:

I apologize if I didn't explain my self properly.
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Re: Method of controlled imbalances and gda...

I have moved this discussion here on the suggestion of a board member. Please continue discussion as needed here. Thanks.
Re: Maracyn/gda experiment...

I should not add any PO4, correct? or should I keep it around 0.5ppm?`
When you use the Kno3 generic protocol you should not add anything else (control algae approach).
About Po4, I think that you should add what your plants needs (Fertilizing approach).
I think that there is a mistake about keeping Po4 and other macros in rigid values like 1 ppm Po4, 10 ppm No3, etc.
There is a general misunderstanding about fertilizing. If you test and you can read 1 ppm of Po4, there is something wrong, probably you are adding too much Po4. I think that the best is to keep tha tank close to GSA.
I had an aquarium with only marsilea crenata. In that tank I used to add about 4 ppm of Po4 a week and I always was very close to GSA. This was because the marsilea crenata uptaked all the Po4 I added.

So you are saying the amount of potassium in the KNO3 should be adequate for the tank?
This is a general rule because some plants needs more K like microsorums.

I still stay with my idea that potassium which is not really consumed by the plants, certainly not like phosphate and nitrate, build up in the water column to toxic levels for algae
mmmm, yes and no. I think that the problem with potasium is that plants need just a little. If you add too much then plants uptake it. This is what farmers call "luxury consumption". When this happens you run out of No3 and then there are proper conditions for algae. I don't like to use the word toxic related to algae because algae only blooms when there are proper condition.

I believe the potassium is used by the plants more as an essential role in water status within the plant and turgor pressure of its cells. Also K is involved in the accumulation and translocation of newly formed carbohydrates.
Potassium is very important, no doubt. If to take a look to the "bible", Sorin explains:

"In the body of plants, potassium is essential for the formation of starch and cellulose. As for the conversion of these substances into glucose. His speech was a catalyst, ie, it performed just by their presence and amounts pequenias not interveninng in the chemical reaction. Ie, directs the reaction but is not involved in it. Potassium is one of many metal catalysts, as opposed to organic catalysts such as enzymes and yeasts that are organic catalysts (alive)"

You can download the Sorin's book from this link:

The book was sold out over 20 years ago and it will never be printed againg (last edition was in 1986), so the copyrights are abandoned.

The best of that book is the Macro/ micros chapter, and lighting. Others chapters are simply obsolets.

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Re: Method of controlled imbalances and gda...

Okay...let me try to understand this concept in simpler term.
Ok, let's do it:

The MCI is a method of algae control and fertilizing.

Algae control approach:

1) Remove the GDA.
2) 50% water change
3) stopt fertilizing at all
4) Check your Co2, it should be at the maximum tolerated. PH/KH charts are useless. The best is to see how your shrims behaves. Increase slowly the amount of Co2. If they try to escape there is "real" 35 ppm of Co2. Then, you tune it a little less, use a filter or whatever to get away the Co2 from you water. If you have an electronic kit (Milwakee or similar) its much easier.
5) Add Kno3, 1 gram every 50 gallons per day during 1 week.
6) Day 7 50% water change

If after 1 week you didn't reach GSA, continue another 7 days but add 2 grams of kno3 every 50 gallons.

Fertilizing approach:

The amount of kno3 you used to reach GSA is the real consumption of your aquarium. This is amount you should use per week of Kno3.

GDA is related to a complex imbalance that involves Ca and Po4. So, don't worry about CSM+B.
You should add less Ca and Po4. Try adding 1/3 of the dozing you was using.

About Po4, I think that you should add it only if it is necesary. If you reach GSA the I suggest you add 0.1 ppm and see what hapend next week. If you reach it again you add 0.2 ppm and so on until you find the real consumption of your aquarium.

I'm using the EI method.
You can use any method you like. But you should understand that all aquariums are different because there are differents combinations of plants, light, Co2, fish, etc. Every plant specie has unique needs. For example, marsilea crenata needs tons of Po4, microsorums needs k, Po4 and it's very sensitive to chloride. Glosso needs tons of No3, etc, etc.
This is the reason why rigid rules doesn't work. Of course you can solve many problems with Excel but this only hides the real issue.

So after a major trimming, you'll have to cut back on KNO3 to find the optimum again or else you'll get GDA. Correct me if I'm wrong, but it looks like you'll have to constantly monitor your levels.
Once you know the real consumption of your aquarium you reach a balance. You don't need to constantly monitor your levels. You should just take a look if you have or not some GSA just before the water change.
But remember that we work with a dynamic balance because the aquarium is changing all the time. The generic protocol of the Kno3 I suggest will help you a lot to know how does your aquarium works. We have been using this method for over 4 years and algae is not an issue any more, not even for begginers.

If you take a look at the CIM, go down until you reach the algae pictures, you'll see that we had identified the most common algae and how to deal with them.

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Re: Method of controlled imbalances and gda...

there is no need to monitor any level since your bioindicator will be GSA, if you do a major trimming you can make a water change and star dosing KNO3 'till you get the GSA and that would be your weekly dose and the rest would be as the EI method suggests.

Isn't so Christian...

precisely. You can use the algae control approach of the MCI and any other fertilizing method you feel comfortable with. Or you can use the MCI as your main fertilizing method. It's up to you, I am not a priest so I am not interested in evangelize nobody with my method.

Re: Method of controlled imbalances and gda...

I downloaded Sorin's book but itsin Spanish and is a pdf.
Is there a way to use the google translator?:-k
There are free programs that transform pdf in text, then you can cntl copy it and translate with google translator.
One website I know is
Anyway, the chapters about Co2, macro and micros is not that long, you can type it.
Re: Method of controlled imbalances and gda...

theres a lot of common sense information here, which is a good thing.
cheers for starting this discussion and its been amazingly civil.

its great to see discussion that involves monitoring the tank by actually using the plants and algae as indicators of the tanks health. you watch a tank long enough, you can begin to find patterns and you can infer what will happen next. I read through this discussion and quite a few familiar things did click.

I dose in excess, but often I do agree that it gets me in trouble and I see it coming.
N - P ratios also get me in trouble. but good trouble.
I hate to see plants starve, wither, not live up to potential.
maybe I should work harder at trying to find a balance between yield and stability.
but I like yield very much.
Well, I used to cultivated aquarium plant as a living. The place I had was small so I was very interested about efficiency, high rates of growing and, of course, avoid starvation. From that experience I realize that there is a false dichotomy between efficiency and proper feeding. The idea I propose is to reach what your plants are really uptaking. There is no need of having nutrients in the water column that are not going to be consumed with one exception: No3. As soon as you lack No3 you are in troubles.

Re: Method of controlled imbalances and gda...

If you add the macros separated, then you can play with them independently, that's the best!
Depending the plants you have the amount of Po4 you need.
Re: Method of controlled imbalances and gda...

Re: Method of controlled imbalances and gda...

I am really glad about that! :D
Re: Method of controlled imbalances and gda...

I admit to some confusion here as I am seeing references to gsa and gda.
I undertand your confusion. This is because I resume the MCI in a few sentences. I should translate the complete thread, it will take some weeks. Meanwhile you can use google translator. If you go down in the first page you will find many algae pictures, there you have specific protocols to deal with them:

I don't have any green dust algae in any of my tanks but I do have green spot algae in two of my tanks. Especially on (can anyone guess?) my anubias and the older leaves of crypts and a large crinum.
One of the ideas of the MCI is that we are fertilizing plants instead of tanks. Each specie has a different uptake. Anubias and crinums needs extra Po4. GSA is a bio indicator or an imbalance about Po4, a lack of Po4. The protocol for the GSA is:

1. 50% water change.
2. Stopt fertilizing at all.
3. Clean the GSA (We are going to use it as a witness) every day.
4. Add Po4 every day. The doze is a gram every 500 gallons.
5. Repeat #3 and #4 until GSA doens't show up again.
6. The amount of Po4 you needed to stop GSA is the doze you should use per week.
7. 50% water change on the 7th day.

Is this a method for removing/controlling gsa, gda, or both the previous and other types of algae? Or, rather, is it a method for finding a more optimum method of fertilization and the side benefit is a reduction or elimination of gda, gsa, et al?
The MCI is a method for control any kind of algae and for fertilizing. I believe that fertilizing and algae control are 2 faces of the same coin. The algae are bio indicators of your failures, You can't separate fertilizing and algae control.
I look for the GSA in the same way that a blind man looks for the wall at the street with his walking stick. As soon as I find the GSA I know where I am. If I stay close to GSA there will be no other algae. This is the main idea about algae control.
About fertilizing, the idea is that every plant has different needs, so for me rules like 10.1.15 or TB idea about non limiting resources makes no sense. I propose to use the generic protocol of the Kno3 as a way to know the real uptake of your plants about No3. You can use the Po4 protocol against GSA to know exactly how much Po4 you need.
It's just common sense, if you have guest to dinner you should ask how many in order to know how much food you need. You don't ask about how many square feet is the house. The approach that is use in fertilizing is like this, people talks about how many gallons has the tank instead of taking care of the species you have.

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Re: Method of controlled imbalances and gda...

I thought the main reference was to GDA and NO3 uptakes. I thought a similar approach was used for GSA with PO4 - adding PO4 until GSA was gone. :confused:
Newt was right, we were talking about to reach GSA as a way to eliminate GDA and other algae.

That approach can be used with all macros (Fe included) at the MCI. For example, you talk about your 10 gallon tank. You have too much Ca in your tap water and you add MG to compensate it. If you stop fertilizing with MG you have problems very soon. This probably means that you are adding not enough MG. You can use the same approach I propose with No3 with MG. Instead of looking for GSA you are going to look for this algae:

Usually people say that algae blooms because an excess of nutrients, TB says that they show up because a lack of nutrients, I believe that is something in between, they appear when there is an specific imbalance. You can solve it with the Kno3 protocol and after that reviewing you dozing. You can use the algae as feedback, for this reason I don't agree with the magic solution of Excel.

As I said before, the main idea is that we are fertilizing plants intead of tanks. This is another layer in the MCI, to solve algae issues in long term with proper election of plants. You mentioned that your water has too much Ca. Perhaps you should have some plants that consumes priority Ca as rotala macrandra among others.

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Re: Method of controlled imbalances and gda...

Let me see if I have this straight, add NO3 daily until you start seeing green SPOT algae. This will be the measure of NO3 needed to stop green DUST algae?
To stop GDA you should follow the GDA protocol.
The generic protocol of Kno3 measures the amount of Kno3 you need per week in order to fertilize properly with that macro and avoid algae.
Re: Method of controlled imbalances and gda...

This is very interesting. I think I will try this on my 90g tank. I have intermittant problems w/ BBA which I resort to killing w/ Excel.

One question--I gather you are suggesting that if I follow this method to find the KNO3 level required to induce GSA (green spot algae) then I can maintain this level and prevent the BBA from returning?
You can stop bloom and prevent BBA returning with the Kno3 generic protocol. But BBA is a vague. Wich one do you have?

This one is related to an imbalance that envolves too much Ca (related to MG) and Fe.
The generic protocol of Kno3 works great to stop the bloom and you can use Excel to kill it. After that you should a) add more MG or b) add less Ca and add less Fe.

IF the algae you call BBA is this one:

Then you have an imbalance related to Fe and micros. The solution is the use the generic protocol of Kno3 + Excel. After that, you should add 1/3 of the micros + Fe. This algae is typical when you used CSM+B.

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Re: Method of controlled imbalances and gda...

`I think Christian is saying once you see GSA while dosing no3 daily that the amount you dosed to that point is what you should use as a starting point for a weekly dosage. Maybe the plants with this amount of kno3 and proper co2 have now depleted the phosphate.

Once you have your KNO3 figured out you are then riding on the edge of GSA which usually means your low on phosphate right? Now you start dosing along with you new weekly starting point for kno3 a small amount of phosphate. Say .1ppm per day until you no longer see new GSA developing on glass or plants. Ect........
No exactly. If you have GSA then you are lacking Po4 and your plants will suffer because of it. But if you are close, means that your plants are properly fed without algae issues. Usually there is no need of adding Po4. GSA will tell you if you have to add it or not. Depends of the plants you have and their needs.
I used to cultivate anubias in monoculture with very high light, I used to add Po4 as salt with my hands and I was always close to GSA. The anubias grew up very fast. The same happend with a noculture of marsilea crenata.

This seems like a logical approach for me because In my experience all algae forms can be beat. I think Christian is just giving a system to help people find the balance (the =/- part of EI) quicker. EI is a system I have used successfully but I have also seen ferts load in excess big time in my aquarium and cause problems for me.
That's the idea! The MCI born as my (algae) feedback of the EI. After that I abandoned the EI and I developed the fertilizing approach of the MCI.

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Re: Method of controlled imbalances and gda...

I have read that CSM+B can not have enough iron (or if I am not dosing enough) so I have recently (this week) begun adding Seachem's Iron suppliment. Too soon to tell if this will help though.
The iron fashion....I think that the problem with CSM+B is another but not the lack of Fe.
May you please post the link yo mentioned?

A couple questions:

1. During the KNO3 protocol should I continue to dose micros or potassium? (I am currently dosing both in addition to KNO3, no PO4 currently as my tests indicate that I have more than enough from feeding my fish).
No, you should stop fertilizing at all, only Kno3.
About the Po4, you should have plants with priority need of Po4. Marsilea crenata is the best choice. As soon as you have a carpet of marsilea crenata you will need to add Po4.

2. After I find the correct KNO3 level what amount of micro's should I add? You specify 1/3--I am not sure if this means 1/3 of the KNO3 amount or 1/3 of my current dosing or something else entirely.
I mean 1/3 of the CSM+B. The amount of Kno3 you need for reach the GSA is what you need por week.

Each algae has the same Kno3 protocol but with some extra tip, for this reason the best is to check the spanish version until I translate it.

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