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Confusion about EI and other myths

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  • Confusion about EI and other myths

    As this method has become popular, it also has had growth pains.
    1. It was never meant to be applied rigidly.
    2. It is a simple concept, provide non limiting nutrients without having to test to do so.
    3. Adding non limiting nutrients provides the plants with optimal nuterients so folks can rule out deficiencies
    4. Precise plant nutrient Deficiencies are not known for most every aquatic plant. This requires a high level of testing and things like fish food, sediments and other potential confounding factors come into play.
    5. If you have lower growth, lower light, then you can make safe assumptions like using less nutrients, again, refer to #1.
    6. Algae are not nutrient limited in aquariums with fish and plants. Argue this all you want, but you need to research and see what types of nutrient levels will limit algae. They are extremely low and any fish waste and plant decay, leaching etc is more than enough to supply algae with all they need.

    7. 90-95% of all algae related issues are due to improper use of CO2.

    8. 90-95% of all algae problems are related to improper use of CO2.
    There is a good reason to repeat this because folks will forget and blame the nutrient dosing method(and this issue is not limited to just EI, every other dosing routine has the same issues).

    9. Measuring CO2 carefully is not easy. It varies, it's influenced by circulation a great deal, it can change 10X in concentration in less than 30-45 minutes.
    No other nutrient can change this rapidly, nor is critical to every other nutrient. Algae take advantage of this variation to germinate and establish.
    Be very careful in assuming you are 110% positive you have enough, instead, rule out everythign else first, then go about tweaking CO2 and do so slowly, never rush or get impatient.

    10. In general, less light is better than more for every method using CO2.
    This reduces CO2 demand, if you use higher light, consider having methods to reduce it, control it if any issue come up.

    11. EI rules out nutrient deficiencies. While this can rule them out, many find that after adding non limiting nutrients, they still have issues. EI is not solely about nutrients, if the CO2 demand was limited because there was not much PO4, now the CO2 demand is greatly increased. If the CO2 is not also increased to account for this change, then it can lead an aquarists to incorrectly assume that it is the PO4 that is causing the plant or algae issue. However, it is a secondary effect. If the CO2 was controlled correctly in the test, then the algae/plant issue would not have occurred. Such error/s in logic cam lead to false assumptions/conclusions.

    12. Make as safe assumptions as you can.

    13. Test if you want along with EI. Some do so to get a feel for their aquarium, then no longer test if they are within the target(theirs or EI's etc) ranges. These are choices you make/trade offs and you decide if they are worthwhile for you.
    There is no rule that says you cannot test. I suggested testing along with water changes in the past(see 1996-1997 list of levels of parameters thread here). However, testing correctly is not been one of aquarist best traits
    These are cheap test kits and with poor resolution, so it is wise to calibrate any test kit before relying on any data obtained from their results. Even 10,000$ lab test equipment is calibrated, this way we know the results are accurate.

    14. EI is not based on flowery language, perception or marketing schemes. It is not based on faith. It does not disparage other methods. The results are testable, the concept come from PMDD and the math is even in there as well, I simply posed a few graphs.

    15. EI is specific to the water column source of nutrients, however water does diffuse into sediments and can become a source of nutrients to the roots as well.
    This does not preclude aquarist from using root sediment sources as well in conjunction with water column fertilizers.

    16. Ratios. Hot topic and few really understand anything about it and why it does not matter. Epstein and Bloom are two very well respected researchers on this topic and it really gets down to limiting vs non limiting levels much more than a ratio (see their text: Mineral nutrition of Plants, Principles and Perspectives, 2005). Ratios can save the farmer spending 1000$ on fertilizers and reduce their runoff waste, however, aquarist do not have issues here and the cost is insignificant. Still, a relative range of ratios is not bad either, but with the wide range of species kept and each one having their own set of growth rates, nutrient demands, this seems very difficult to apply in a general way.

    17. RR or Redfield ratio, often discussed and cited and folks make a mistake in mass vs atomic number of atoms. A ratio of atoms, number, is 1 P for each N according to marine algae in Redflied's paper.
    This is not mass.

    P is 30.97 grams per mole
    N is 14.01 grams per moles

    To convert to mass, you need to multiply N by 2.2, now the RR is 7:2 1, or about 10:1 for NO3/PO4.

    Still, this is just what is available from upwelling in ocean systems and is typically under extremely high light, full sun etc. The system becomes limiting after prolonged algae growth.

    This is radically different from what occurs in freshwater systems where aquatic plants are involved. FW plants have different ratios, different nutrient sources and cycling, as well as being able to concentrate nutrients from their external surroundings at a much high gradient internally.

    18. Inhibiting levels of nutrients, the upper bounds. Generally, this is from osmotic conditions, too much salt basically. Hoagland's modified solution is very rich and is a non limiting nutrient solution. EI is just a similar idea but on the lower end for aquatic plants, above the limiting ranges but not nearly as rich.
    Hydroponics and Hoaglands solution has a very long history and test/research background for support.

    EI is no where even remotely close to these levels of inhibition.

    19. Less light = less demand for nutrients. You can go too far and get so low plants will not grow no matter what the CO2/nutrients, however, it's a very useful way to control the rates of growth for an aquarium and also to control algae until the conditions are corrected. Many have issues with CO2, so using less light makes targeting a good stable CO2 level much easier than say higher light intensity. Thus limiting light makes the most logical sense, not nutrients and CO2 for algae control, for stability, for CO2 issues/nutrient issues, for control of growth rates, for less electrical use, reducing heat, reduction of any and all waste.

    20. If the CO2 is not properly added, then EI, nor most any method(unless it limits a nutrient so much that CO2 decreases) will help you. Severely limiting PO4 can reduce CO2 demand, but can be difficult to keep doing. Might as well just use less light, since that's where all growth starts.

    You see?
    Lots of CO2 talk, very little about nutrients............

    21. It is an INDEX, any index simplifies reality, thus has inherent limitations like any index or indices, such as the stock market, economic forecasting or species diversity. Any attempt to compress complex data into a singel index will sudffer some loss of information.
    that's why I chose to refer to it as EI, not something cheesy like Tom's wonderful magic potion of plant growth. This index is fairly robust because of what went into the general concept, it assumed the highest possible rates of growth at the upper limit. So we will essetnially never run out of any fertilizer. EI does not nor any other nutrient method done much with CO2 or light(EI just used an upper possible bound with respect to light)

    So if you mess up CO2, which most/many aquarist do at some point(either application or measurement errors, assumptions), then algae, or poor results are not indpendent of light and CO2, they become dependent.
    A nutrient method cannot be judged unless those other two main players in plant growth and fully addressed, this has long lead to confusion and blame.

    Most hobbyist just want good plant growth and no algae issues.
    They rarely do test to illustrate and confirm independence in such test systems and experiments.
    A good way to do it: have a nice tank without algae and good growth of plants.
    That makes the best control for falsifying something, but will not tell you what something might be with certainly.

    Tom Barr

  • #2
    Feel free to post other confusions, myths and tips.

    Tom Barr


    • #3
      Extra iron = deformed growth. Why?

      Properly speaking a question why every time adding ferric gluconate (Fe=0.01-0,1 ppm daily) with TE (Flora pride) lead to deformed leaf growth of some plant species (Hygrophila polysperma). Suspension of extra iron cures of a disease.

      What is that? Deficiency of any elements or excess of Iron?
      Last edited by Andrey_V; 10-23-2008, 01:12 PM.


      • #4
        Originally posted by Andrey_V View Post
        Extra iron = deformed growth. Why?

        Properly speaking a question why every time adding ferric gluconate (Fe=0.01-0,1 ppm daily) with TE (Flora pride) lead to deformed leaf growth of some plant species (Hygrophila polysperma). Suspension of extra iron cures of a disease.

        What is that? Deficiency of any elements or excess of Iron?
        No, I add lots and lots of traces and have never once found this result. With 300 species and hard, soft tapwater, high/low KH/Gh etc.

        This is a classic secondary effect.
        Twisted tips was all about Ca+ according to many.

        Yet not one person has ever showed definitively "why". I've lowed Ca++ down to 5ppm or so, pretty low, no twisted tips............

        Rather than thinking you are suddenly the newest discovered of some myth that is now debunked, go out and see if other folks are adding the Fe at high levels, I'm sure I can add and likely do add a lot more FE than you do. I also have high Fe in the sediment.

        I do not have twisted or stunted tips on even the most sensitive picky species.

        So that as a direct cause can be safely ruled out.
        Now, about your problem, secondary effects can be caused by a dozen or more possible things IME.'s typically from CO2 if EI is applied. EI seeks to provide non limiting nutrients, all of them, not just Fe.

        So if you have done that, then you will want to look at consistency over time and good CO2.

        I have seen CO2 cause twisting in a dozen or more species while leaving other species unaffected. I added a bit more CO2, the issue went away, the dosing was EI and the dosing was consistent the entire time. I've done perhaps 30 times over the years now.

        Plant no longer has carbon backbones to make new tissues with, this will affect the new growth dramatically. I'd look there and then try the higher Fe .

        If you step back and think about it, correlation does NOT imply cause.
        Why migth some folks not see this(most), but you do?
        This would lead me to go back and rethink my conclusion and look elsewhere for a "cause".

        I would have enough info to falsify my conclusion and would need to make a another cause to test out and try and falsify.

        Tom Barr


        • #5
          In your experience, it seems that most if not all issues boil down to improper CO2 implementation. Perhaps a formal post on the proper way(s) to implement CO2 is needed? (unless i missed it scanning through posts on your site)

          I have twisted leaves as well(on broad-leafed ludwigia) - I was about to assume that my fault was low Ca. I will try raising CO2 a little bit more first. I do not dose very much iron - 3x a week I dose seachem comprehensive (so i guess too much iron isn't what is affecting me)



          • #6
            While CO2 is often the "Root of all evil" as some seem to suggest, there are other factors that are not light and not nutrients.............

            Simple things often, something was clogged, left trimmings in the tank, tossed some in and never got around to planting the stems for a week or two, Slacked on water changes for 2-3 weeks, have not cleaned the filter much, need to prune more often etc.

            Gardening and growing plants is not just CO2/light/nutrients.

            There's no easy cheap method to nail CO2 right, unlike nutrients.
            Light is easier than CO2, especially when a decent PAR light meter is a mere 149$ now...........

            So CO2 is mostly some testing, watching plants the most/fish as well, a lot of experience and tweaking.

            Unless you know what the max plant growth looks like, how can you compare it to anything else? Many folks think max growth is anything that does NOT have algae, anything beyond that is inconsequential for many folks.

            You just want the twisted leaves to stop.
            The rest is not of any real concern.

            But many will not find any comfort without doing things step wise if they want to really know why.

            They can however, just keep messing and fiddling haphazradly and may or may not get lucky.

            Then attribute it to a dozen or more things they did, or perhapos just one and never are sure of what they really did or not.

            I know what the nutrients look like at low and at higher ranges, certainly into the very excressive ranges.

            There's no smoking gun there.
            Some claim certain species are "more sensitive", this too has been easily to show to be false over typical common higher ranges. It's when we get really far out, to the point where the salt stress becomes a factor, that such issues start becoming much more an issue.

            Plants compete for CO2 with eachother.
            So many plants may stunt, while the others do just fine.
            Limiting CO2 affects new growth the most and the most dramatically.
            Many species are very aggressive and have little issue with lower CO2, others are pretty wimpy unless it's kept high all the time.

            I think many folks think excess nutrients cause issues for them because of correlation, not cause. They add say a limiting nutrient, say in your case, you where not adding enough Fe.

            Adding more Fe took that limitation away, allowing faster growth, more plant biomass and then the limitation switched to CO2 for some species.

            You did not have enough CO2 under non limiting nutrients, however, you did with limiting Fe(or PO4 etc). K+ can do this as well.

            So many folks dial back their nutrients and assume that it's due to "excess". Such observations however do not show nor prove "cause".

            If they provided non limiting conditions for CO2 in both cases, now...........we see that these same nutrients do not cause stunting in the same species, in the same tank etc.

            So it cannot be due to the nutrients in that case. Can it?
            So why would it be the case in the other tanks where the CO2 was too low?
            I was never the nutrients, it was the CO2 that caused the expression of stunted tips.

            You cannot say nutrients did it in both cases because it did not occur when the higher CO2 was added.

            So it must be another reason, likely CO2.

            The logic is pretty simple, but you need the observations and do a it a few times back and forth. If not and all you have to go on is the problems you have, without trying to address things like CO2 which is a hard parameter to measure, then you will always believe the nutrients are too blame.

            This flawed logic has gone on in the hobby for many decades.
            I'm different and folks think I'm clever etc because I adhere to logic and step wise approaches, no, I'm not. I just try and find what is causing things by ruling the likely suspects out.

            There may be many other possible causes for stunted tips, however, I do know what does not cause stunted tips pretty well. Then I look elsewhere and not waste my time on that.

            Tom Barr


            • #7
              Believe me this is not CO2 issue in my case. CO2 is more then enough there. I told you about extra Iron level rather than TE amount. Adding more Traces (2x, 3x10x) drive to great result, however dosing TE with Fe++ (whether it ferric gluconate or Fe2SO4+EDTA) surprised me with leaf curling. Do not refer me to the other water parameters. They are Ok. I use TE method about one year with great success but tried to add some Iron to improve the color of red plants. I need not have done it


              • #8
                Originally posted by Andrey_V View Post
                Believe me this is not CO2 issue in my case. CO2 is more then enough there.(
                Personally, I thought the same thing in my tank. But until I improved my flow by adding some circulation pumps I had no idea that CO2 was not being adequately dispersed. Some areas and plants just weren't getting as much CO2 as I had assumed they were.


                • #9
                  I have plenty of Fe and can add it with 4 different chelator types, the KH is a little above 1 degree, or about 20ppm.

                  I've added up to 1ppm daily for several weeks, I've not noted any curling with the most sensitive fincky plants.


                  I really have heard this all before, about 12 years ago when I suggested folks add more trace elements, back then, everyone claimed adding excess Fe cause algae.

                  Today, that's hardly a myth that's talked about.
                  Folks have ben adding a lot of traces, as well as spikes of Fe alone.
                  This is common and few have seen issues with it.

                  I do it and do not see the same results.
                  If you accept that must be the cause, how can you explain that when I do this same thing with dosing, I do not get those results as well? I even go higher than you have.

                  For this to confirmed and to be true, I would have to see the same results.
                  With DTPA, and Gluconate, I cannot say I have however, even at 1-2ppm of Fe.
                  Hydrilla will do better even at 6ppm of Fe.

                  I cannot say/explain why you have issues with curling, however, I can say what it is not causing the issue

                  Hygrophila is a fast growing species, adding one limiting nutrient can cause another to increase it's demand, leading to a deficency, but you might end up blaming the wrong nutrient.

                  This is why you can have a dozen different tanks all with different reasons, having a similar result.

                  Unless you safely account for all the other nutrients, you cannot be sure. The test needs to be independent of those other possible issues. If not, you cannot say much or conclude. EI targets a higher ppm than any other dosing for aquariums, but it's still low compared to Hydroponic nutrient solutions.

                  Still, Fe can be an issue for some folks. I'd suggets switching to a different brand, say Tropica or use DTPA. You should be able to dose more without issues. Sometimes the harder water(KH) can cause issues for some folks using weak Fe chelators.

                  Might be that.
                  Hard to say without more details.

                  Tom Barr


                  • #10
                    Here's some examples of high Fe:

                    This is easy since I've been adding a lot of Fe for 2 decades.Also, see SFBAAPS site, they have many tanks with high traces and many of the AGa older contest winning tanks also, from 2000-2004 or so.

                    Where are my stunted plants?

                    I can consistently add 5mls of a specific liquid daily to give the same dose precisely each time.

                    I cannot do this with CO2, I only assume that the CO2 is the same, maybe it is, maybe it is not. If I test well and do not have any test related issues, then perhaps, even here, I need to test often throughout the day to make sure it's good all the time the lights are on.

                    It's not nearly as easy or as simple to rule out CO2 as nutrients, yet many try to and act like everything is all about nutrients. The more I learn the more I can see it's about light and CO2, I can measure and compare light well, it's stable etc, nutrients as well, this only leaves very important variable that's highly fickle.

                    From there, you can slowly tweak it and dial it in to get good results, with high Fe dosing.

                    So high Fe alone is not the issue because if it truly was, why are my plants not showing the same symtoms by adding high Fe?
                    Where are the results from this hypothesis in my tanks if what you say is true?

                    I know I am adding high levels of Fe. So that much is clear, why you have issues, I can only speculate, maybe some other issue you are not seeing etc.

                    I cannot rule out every potential issue some might have, only what I can test and know one thing at a time. In other words, I know what it is not causing the stunted growth.

                    It cannot be a direct issue with Fe.
                    Something else has to be going on.

                    Pics show tanks from 1 KH to 4 KH to 6 KH to 11 KH.

                    Tom Barr


                    • #11
                      Can someone please identify that red plant(s) in the first two pics in Tom's last reply.


                      'When something's not right, it's wrong'. Bob Dylan

                      Current 220 scape



                      • #12
                        Ludwigia Pantanal.

                        Which I want eventually......


                        • #13


                          Makes sense it is a Ludwigia as it resembles my L. inclinata cuba

                          I can see why you want it and it is now on the TOP of my to-get list...

                          I had stayed away from the red plants while I got my tank straightened out and now feel ready to try some other species.


                          'When something's not right, it's wrong'. Bob Dylan

                          Current 220 scape



                          • #14

                            I have some arriving this week along with some Ludwigia 'Araguaia'. Took me quite a while to find someone to sell me some.

                            Putting it in my 24gal Aquapod that's now my high-tech tank. Couldn't deal with my 125 being the high-tech one anymore. It needed trimming at least 2x weekly - something I'm too lazy to keep up with for long.


                            • #15
                              Well, that pant is really weedy, 4-6" a week of growth, I only have a couple of stems now. I look for easier to grow plants that are not picky, respond well to how I like to care for them.

                              That reduces the labor, so does using less intensity and duration at high intensity, makes CO2 easier to dose etc.

                              Hard scapes make the design look and stay nicer over time also, they do not ""grow".

                              My client in LA with the behemoth has gone this route after suffering for years now hanging bat style to prune

                              Lotta damn work.
                              Amano is not that different either.
                              But there's a time for good gardening work to get a look you want, just do not have all large tanks full of higher growth plants. You will get overwhelmed.

                              Tom Barr