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Testing for EI

Andrew Butler

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Joined
1 Feb 2016
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Location
Banbury, Oxfordshire
I will be honest I haven't fully got my head around the EI method but am understanding the basics!
How do other people go about testing? - By that I mean
How often do you test if you do at all?
What test kits do people use? - brands would be nice, I know hanna make some excellent handheld test kits but not for nitrate or potassium.
 
The basis of EI dosing is no testing required. You fertilize at optimum levels, and the regular WC flush the potential toxics away before they get to toxic levels. Cost more water but save money testing water with unreliable expensive test tests.

Lots of folk use the dry ferts from aquarium plants foods I linked you to the starter Kit, great place to start
 
Hi all,
How do other people go about testing? - By that I mean How often do you test if you do at all?
The idea is that you don't have to test, EI supplies the mineral nutrition the plant requires, you add CO2 and plant growth is only limited by the intensity and duration of the light period.

I'm not an EI user, but it was the difficulty in getting consistent, and accurate, water test results that led to the development of both EI and the Duckweed Index. With EI you add an excess of nutrients to ensure that nutrient levels don't limit plant growth, but you have to ensure that CO2 distribution and tank maintenance are spot on to avoid problems with algae, and you use a 50% weekly water change to remove organics etc. from the tank water.

Have a look at <"Good algae article">.

cheers Darrel
 
Hi all,
Reading some articles it refers to levels you would only know by testing so is striking a balance just done by eye?
Older members may be able to correct me, but I think EI was developed by Tom Barr ("plantbrain") who would have had access to the <"University of California (Davis)">, and would have been able to get accurate values for the parameters he was interested in.

You can get accurate parameters for any water sample, but you need <"appropriate analytical equipment">.

cheers Darrel
 
the regular WC flush the potential toxics away before they get to toxic levels
EI supplies the mineral nutrition the plant requires
How about EI and nutrient based soil like ADA-soil?
Because those soils are very nutrient rich based; is there a change for overdosing or other problems?
It's written that the regular WC flush the potential toxics away before they get to toxic levels. But, don't you get a nutrients build up because the soils attempt is to buffer the nutrient provide by EI?

I know thats is almost impossible to damage the plants by high levels of macro nutrients. But it's the micro's I'm worrying about.
At they end of the week there is a reset of parameters by WC but the plant have been all week in a toxic environment (when the soil is saturated with nutrients)
Thoughts?
 
The levels never reach toxic levels and the AS buffers the levels too giving more room for error.
If the AS is saturated it buffers nothing but your levels still safe. If AS getting exhausted it mops up the excess from the water column.
AS also buffers some of the soluble waste products in the water column too

Sent from Mountolympus via neural interface
 
Hi all,Older members may be able to correct me, but I think EI was developed by Tom Barr ("plantbrain") who would have had access to the <"University of California (Davis)">, and would have been able to get accurate values for the parameters he was interested in.

You can get accurate parameters for any water sample, but you need <"appropriate analytical equipment">.

cheers Darrel

It seems he used Hach and Lamotte test kits in developing EI. Then, around 2005, he used a colormetric multiparameter spectrophotometer.

https://barrreport.com/threads/the-estimative-index-of-dosing-or-no-need-for-test-kits.52/

Note: these ranges and test in this article used Hach or Lamotte test kits and where checked against known standard solutions.

The need for such precision is not needed as plants have a very wide range of nutrient concentrations (BarrReport volume 5,7 and 8, 2005) that are above the deficiency level before excess nutrients level become problematic (see figure 3). Today I use a much more sophisticated testing method than a Lamotte or Hach test kit, I use a colormetric multiparameter spectrophotometer...
 
BTW, the post in the link above was posted by Greg Watson but Tom wrote it. Hence the word "Copyright Tom Barr 2005" at the end.
And who else would use "where" in place of "were" (and "CMS" in place of CSM). :angelic:
 
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Thanks for the input everyone
I did have a read into it but found some references to increasing/decreasing doses accordingly which I'm unsure how you assess easily without testing and also when making elements up comments something along the line of 'it doesn't matter if you use a heaped or level teaspoon so long as they're all the same' - surely that would mean each ml of solution would be of a different strength?!
The method does aim for certain parameters and I just question how people know things meet them or thereabouts? I'm not trying to be clever just curious over something that to me at least seems obvious.
 
I just question how people know things meet them or thereabouts?

Always good to question IMO then you understand better. Answer to how folk know it meets the requirwments -based on the results of others eg great plant growth and great looking tanks - so copy what they did Ferts wise and the plants should grow, if not why Flow, turnover,substrate, light may be an issue, local water chemistry etc
 
That's the thing local water plus differences in concentration can make that gap even bigger, then the EI system seems based upon a particular light level and plant demand so thought testing to get yourself at least somewhere near would be widespread.
I've got the answer to what it seems other people do; I know the parameters aimed for so if I feel the need I can do some testing.
 
When you do regular water changes, the ferts do not keep rising forever. There is always a capped limit. For example, if you dose 20 PPM of NO3 a week and do 50% water change every week and the plants use none of it. The NO3 in your tank will never exceed 40 PPM (2X), regardless how long you run the tank. 4X for 25% wc, 1.5 for 66% wc and so on. And if your tap contains high NO3, you can adjust it.

Yes, you won't know your plants uptake rate. But you know the amount of ferts (PPM) you dose. If the theoretically accumulation is within safety level, it should be fine for the fish, without using a test kit.


'it doesn't matter if you use a heaped or level teaspoon so long as they're all the same' - surely that would mean each ml of solution would be of a different strength?!

Where did you get that? Yes it does matter. However, if you do something long enough, you will kind of know what you're doing. May be the heaped spoons of that person means it will be 30 PPM a week instead of 20. Which is still within EI range. BTW, I use a gram scale.
 
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Where did you get that?
I will have to have a look back through but as with everything I realise this is not what the estimative in EI stands for! - I agree weighing it could work easier.

the ferts do not keep rising forever
I understand the maths just surprised people don't test from time to time or at least in the beginning to see if they are supplying anything like the right quantities- it could be insufficient too.

I've said my piece and I'm not trying to argue with anyone, I'm the uneducated one here and that's why I asked the question. I've taken things on board and going to have a read through of the links in detail.
 
Way back when (even predating the "Barr Report" ..... who else remembers TB hanging about on the APD mailing list, asking loads of questions, then contributing to discussions, then dominating discussions, then finally setting up his own "pay up front" website ;) ) actual.weights of the compounds were used such that concentrations of stock solutions were known - so if you wanted 5ppm X in the water column, it was easy to calculate the volume of compound X stock solution needed.

Then one would/could check the level of X in the aquarium using various test kits - with a strong preference for certain branded test kits which included reference standards so that one could check accuracy/precision of measurements.

Of course actively growing plants will consume X, so testing the level of X in the water column, just after addition & then over time, was done so as to have some idea of what to add when to a given tank.

I was running a million phosphate (& other) assays back then & sceptical of the quality of aquarium trade kits & had access to analytical equipment & various reagents, so amused myself with standard curves & such .... & found those test kits weren't half bad - not 3.62 ppm nitrate accurate, but 5, 10, 20 ppm, & dilute your 20ppm sample by a factor of 4 & measure 5ppm well enough
Test strip reagent pad chemistry also yields pretty decent data - IF handled & stored appropriately (& one got the brand right)

I read a lot of anti-kit dogma on forums, but very few details of how these kits "failed" :confused:
or what the supposed interfering compounds are :wideyed:
( & there's an amusing faith in pH values even when the measuring probes have had no maintenance or calibrations done :) )


I don't test anymore - but that's just because I'm lazy :oops: - I also just grab a bottle of Tropica's finest when I want to "feed" my plants
I tend towards sensitive fish (mostly wild caught) & (in)bred pretty shrimp lines, so I run my tanks lean with moderate CO2 & lighting
I do occasionally dip a strip reagent stick just to confirm that my tap water is still pretty much the same as my tank water
 
I understand the maths just surprised people don't test from time to time or at least in the beginning to see if they are supplying anything like the right quantities- it could be insufficient too.

EI is to oversupply the ferts but still within safely level. So that you don't have to test to check if something is short. Initially, curious people (me too) still tested, then they stopped after a while. For me it was because levels (hobby grade NO3, PO4 test kits) were as expected.
 
I have had a further read and I think things are a bit clearer?!?!
Am I correct to think you don't add a particular individual trace element but use pre concucted ones: potassium nitrate, potassium phosphate and magnesium sulphate which contain the potassium, nitrate, phosphate and magnesium which make up the macro nutrients then the micro nutrients are the trace elements which is mainly iron?
I'm unsure how everyone goes about sourcing the components, maybe you could help here?
Looking on aquariumplantfood it seems they do things by teaspoon which I'm quite sure is 5ml and I assume they have proportioned the calculations to work with the ones detailed on the link below?
https://www.ukaps.org/index.php?page=dosing-with-dry-salts

Sorry if I seem a bit stupid, reading that link and others at first led me to think you added each element individually which other people might. I'm no scientist so was a bit confused at the chemical formulas too!
 
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