Question of the Day Are we past the Estimative Index way of dosing?

Art

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When I started the hobby, we tried to dose to feed ONLY the plants but not algae. We all thought that phosphates were evil and having just a bit too much meant a war with algae. Then came Tom Barr with his Estimated Index idea and said, "forget that". Just dump plenty of complete fertilizer into your tank so plants grow healthy and the plants will outcompete the algae. Boom!

This meant easy dosing but required 50% water changes every week. Not too bad in the freshwater world especially if you use tap. But a real pain if you use RODI and don't automate it in some way.

Over time, aquarists have backed away from EI dosing and now use some sort of hybrid dosing that matches what their tank needs to grow healthy plants.

Has the hobby grown past EI dosing?

 
I think the new dosing techniques are very complicated, I believe they need a lot of tests and calculations, and we must rely on devices to do this in an automated way, it is not for the normal hobbyists. I think the only justification is when we have a huge tank and everything is already measured and calculated automatically like Takashi Amano 40m tank for example :)

For me EI and water changes is the way to do it, plus of course monitoring algae and take fast corrective actions before it spread
 
I think EI type dosing will remain relevant for quite some time into the future for two main reasons.

1. For the majority of hobbyists its tied to lifestyle. Because of the excess one doesn't have to dose daily or worry about things bottoming out as quickly. Other than the weekly water changes dosing is pretty simple you don't have to worry about being so precise.

2. No testing. A large appeal is the reduced need for testing. Since there is a wide variety of acceptable fert ranges and you shouldn't be bottoming out (EI excess.)

It's only natural, if you become more dedicated to the hobby and spend more time with it, you will tweak things as you move along, but for the majority of people and the majority of plants it works just fine. I know a lot of literature states that EI is best for a heavily planted tank, but I have two tanks running right now. One is minimalist and the other heavily plant and I pretty much dose the same for each and there is no visible algae in either tank. I've measured PO4 at 5ppm and NO3 as high as 80ppm. Leading me to believe that maintenance is even more important than one thinks. It's within the maintenance routine where algae finds the opening.
 
EI style dosing is just a name given to provide ample amounts of nutrients into the water coloumn. . There are many ways to do it for example EI daily dose, Half EI etc. In essence its a water coloumn dosing approach larding on the nutrients.
If you really break down all the commercial fertilizer amounts they are within range of EI style dosing. I don't think anyone doses exactly what the bottle says anymore. You can scale up or down depending upon what your plants are doing.
Now dosing lean is a very deceitful way of dosing. YES I SAID DECEITFUL. People do it to try and color up their plants by starving them of nutrients. Or to have slower growth so as to not trim as much. Yet another reason less water changes. The thing many don't realize (and a lot of the bigger name people in the hobby, including aquascapers) preach this approach of lean dosing, but they do not tell you or will not tell you that their substrate is very nutrient rich. That is the secret. Dosing lean with no soil nutrients is a recipe for disaster waiting to happen.
 
Has the hobby grown past EI dosing?
I am testing this theory right now. For quite some time I have been at less than full EI levels, but am slowing inching things back to full EI.......and maybe beyond. Really just to see what happens.

And EI was never really meant to be a strict number. It should be considered a starting point. Many tanks will do great at lower than EI at some percentage. Much depends on the amount of light provided and the type of plants in the tank. I think more important are the large water changes and then replenishing nutrients. It's more work but is a hard combination to beat. Plants love it.

There are some other changes we have seen to standard "EI" as well. It was set up so that you perform a large water change, have a day of rest, then dose macros and micros every other day. IMO this a flaw in the system. When you change a large amount of water you remove a large amount of nutrients. 50% water change and nutrients are cut 50% too. Then you dose throughout the week and levels gradually rise peaking right before the next water change. Then they drop again.

Some sensitive species do not like sudden changes like that. They prefer stable levels of nutrients. Several years ago I started front end loading all macros right after a water change then dosing micros daily. Just a single dose of macros once a week. Tank nutrient levels are much more stable and so is the tank.

Since that time I know many, many people who have switched to front end loading macros. So things do evolve over time.
It's within the maintenance routine where algae finds the opening.
+1 on this. People love to play whack-a-mole with ferts to fix algae. Rarely works.

Better maintenance and dialing in CO2 has much more impact.
 
Several years ago I started front end loading all macros right after a water change then dosing micros daily. Just a single dose of macros once a week.
So I am one of the ones that started doing the same thing. How are you dosing micros, @GreggZ?

I had my Neptune Apex set to do a full dose of macros right after my water change (i.e., I would hit a button to do it). Then the doser would deliver micros on a daily basis.
 
So I am one of the ones that started doing the same thing. How are you dosing micros, @GreggZ?

I had my Neptune Apex set to do a full dose of macros right after my water change (i.e., I would hit a button to do it). Then the doser would deliver micros on a daily basis.
I have been making my own blend of custom micros for years now and am dosing daily. I do it manually as it's just part of my routine. Every morning I get my coffee and walk over to take a look at the tank.

I am actually in the process of writing an article about custom micros right now. Trying to take a complicated topic and make it seem easy enough that more feel they can try it.
 
I have been making my own blend of custom micros for years now and am dosing daily. I do it manually as it's just part of my routine. Every morning I get my coffee and walk over to take a look at the tank.

I am actually in the process of writing an article about custom micros right now. Trying to take a complicated topic and make it seem easy enough that more feel they can try it.
That's awesome, Gregg. Please note that you can post an article in the Fertilizer forum. Just select article as the post type and it will provide you with the format to use that. Then others will be able to post responses to it.

Another option is to put it in the Resources section.
 
EI has become a blanket term. The majority of hobbyists following "EI" are not aware of the impact water change percentage has, or what actually is going on with nutrient levels in the water column. And that's normal. Who got in the hobby to worry about ppm in the water?? I didnt!

EI gives you plenty of everything w/o worrying about testing or the <at the time> devil otherwise known as PO4

I know some really good plant growers using "EI"... but they do 70% water changes. Thats not EI. Actual EI calls for 50% wc once a week. Between which you add 22.5 ppm NO3, 3.9 ppm PO4, and 22.5 ppm K + micros which I wont even get into

I change 90%+ water about every 6-8 days. Front load macros for the entire week right after @20/8/30 or thereabouts

Had a guy on TPT recently ask me why I dosed so much PO4 when EI only calls for 3.9 ppm week? That's a good question isnt it?

But here's the thing, standard EI rolls with about 8 ppm PO4 in the water column when you factor accumulation. I change nearly all the water and go back w/8. So not much difference, for sure not as high as it sounds at first glance

PO4 is about the only thing I do run close to EI. Relatively speaking I use less NO3 and more K (EI @50% wc rolls with ~40ppm NO3)

Another thing overlooked is most people using "EI" back in the day when it was the latest thing, were also using Toms GH or cloning it themselves - as was recommended. This adds another 5-10 ppm K to the mix. Or more. Remineralizing RO to 5dGH? You're running 2x K to NO3. So actual EI runs higher K than NO3, but it doesnt sound like it if you just pick the NPK dosages

Short answer: Yes. But most people dont even know what EI means. Its still a good starting point and just getting close to the routine will allow the intermediate hobbyist to have success with most stuff
 
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EI has become a blanket term. The majority of hobbyists following "EI" are not aware of the impact water change percentage has, or what actually is going on with nutrient levels in the water column. And that's normal. Who got in the hobby to worry about ppm in the water?? I didnt!

EI gives you plenty of everything w/o worrying about testing or the <at the time> devil otherwise known as PO4

I know some really good plant growers using "EI"... but they do 70% water changes. Thats not EI. Actual EI calls for 50% wc once a week. Between which you add 22.5 ppm NO3, 3.9 ppm PO4, and 22.5 ppm K + micros which I wont even get into

I change 90%+ water about every 6-8 days. Front load macros for the entire week right after @20/8/30 or thereabouts

Had a guy on TPT recently ask me why I dosed so much PO4 when EI only calls for 3.9 ppm week? That's a good question isnt it?

But here's the thing, standard EI rolls with about 8 ppm PO4 in the water column when you factor accumulation. I change nearly all the water and go back w/8. So not much difference, for sure not as high as it sounds at first glance

PO4 is about the only thing I do run close to EI. Relatively speaking I use less NO3 and more K (EI @50% wc rolls with ~40ppm NO3)

Another thing overlooked is most people using "EI" back in the day when it was the latest thing, were also using Toms GH or cloning it themselves - as was recommended. This adds another 5-10 ppm K to the mix. Or more. Remineralizing RO to 5dGH? You're running 2x K to NO3. So actual EI runs higher K than NO3, but it doesnt sound like it if you just pick the NPK dosages

Short answer: Yes. But most people dont even know what EI means. Its still a good starting point and just getting close to the routine will allow the intermediate hobbyist to have success with most stuff
LOL this post reminds me of years ago when I first got into high tech. I read posts like this and it seemed like gibberish or someone speaking in tongues.

But I can attest that this all makes perfect sense. If anyone doesn't understand something about it.....ask. It can all be fleshed out even further but that is an advanced class and only for those who really want to geek out!:D

This post also makes me glad that @Burr740 has joined this forum. For those that don't know Joe and who he is in the hobby, you should.
 
EI has become a blanket term. The majority of hobbyists following "EI" are not aware of the impact water change percentage has, or what actually is going on with nutrient levels in the water column. And that's normal. Who got in the hobby to worry about ppm in the water?? I didnt!

EI gives you plenty of everything w/o worrying about testing or the <at the time> devil otherwise known as PO4

I know some really good plant growers using "EI"... but they do 70% water changes. Thats not EI. Actual EI calls for 50% wc once a week. Between which you add 22.5 ppm NO3, 3.9 ppm PO4, and 22.5 ppm K + micros which I wont even get into

I change 90%+ water about every 6-8 days. Front load macros for the entire week right after @20/8/30 or thereabouts

Had a guy on TPT recently ask me why I dosed so much PO4 when EI only calls for 3.9 ppm week? That's a good question isnt it?

But here's the thing, standard EI rolls with about 8 ppm PO4 in the water column when you factor accumulation. I change nearly all the water and go back w/8. So not much difference, for sure not as high as it sounds at first glance

PO4 is about the only thing I do run close to EI. Relatively speaking I use less NO3 and more K (EI @50% wc rolls with ~40ppm NO3)

Another thing overlooked is most people using "EI" back in the day when it was the latest thing, were also using Toms GH or cloning it themselves - as was recommended. This adds another 5-10 ppm K to the mix. Or more. Remineralizing RO to 5dGH? You're running 2x K to NO3. So actual EI runs higher K than NO3, but it doesnt sound like it if you just pick the NPK dosages

Short answer: Yes. But most people dont even know what EI means. Its still a good starting point and just getting close to the routine will allow the intermediate hobbyist to have success with most stuff
Thanks, Joe. Very well said and very interesting.

Let me ask a follow on question. Why did you choose 20/8/30?

In other words, how did you arrive at the macros you're dosing?
 
Thanks, Joe. Very well said and very interesting.

Let me ask a follow on question. Why did you choose 20/8/30?

In other words, how did you arrive at the macros you're dosing?
Just by going up and down with various levels over the years. And its not some magical ratio or anything, just what Im doing atm. Taking either one up or down a little wouldnt change much
 
Now dosing lean is a very deceitful way of dosing. YES I SAID DECEITFUL. People do it to try and color up their plants by starving them of nutrients. Or to have slower growth so as to not trim as much. Yet another reason less water changes. The thing many don't realize (and a lot of the bigger name people in the hobby, including aquascapers) preach this approach of lean dosing, but they do not tell you or will not tell you that their substrate is very nutrient rich. That is the secret. Dosing lean with no soil nutrients is a recipe for disaster waiting to happen.
This whole paragraph is spot on. Another thing that adds to the confusion is most of the lean dosing crowd do smaller water changes in the 25-30% range

Nobody ever asks how much water you're changing, just how much are you dosing. Unless you know the former, dosing numbers are meaningless. 10 ppm /week with 25% WC is totally different than 10 ppm /week with 70%. (I know you know this, talking in general)

Not counting the ones running zero NO3 in the water with a souped-up substrate, in a lot of cases there's not as much difference as it seems between the lean crowd and folks dosing a lot more
 
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I am re-reading this thread, triggered by a new thread on another forum.
Some great posts here in ScapeCrunch, worth bumping for new readers.

And EI was never really meant to be a strict number.
EI gives you plenty of everything w/o worrying about testing
EI has become a blanket term.

Too often new hobbyists, or even some experienced hobbyists, make the mistake thinking that EI is a prescriptive method. EI is not a prescription that can be proven right or wrong, not a law, not even conjecture and certainly not a panacea. Its inventor @plantbrain made that clear again and again. It is a method to not deprive your plants from nutrients, stop worrying about algae and testing, and gradually converge to the optimum whatever that may be for one's particular setting or goals. That we now have branched out to many variations of EI is its strength, not weakness.

I am personally not a fan compartmentalising dosing methods, or conflating an over-simplified interpretation of EI with culture or even the credibility of its inventor. Sometimes we must be reminded, because with new hobbyists or imperfect memory same confusion repeats itself.
 
I tailored my ferts to meet my goals, which by design have fallen into the EI category. This may piss people off, but my life doesn’t revolve around my tank and extra ferts keeps my tank from crashing if I’m lax on my WC/maintenance schedule. I fully accept the repercussions that come with this, but I’ve found having more ferts and not less are better for me.

Side bar, those more meticulous and on your game, I envy you. I’m just not at that point in my life, so I work with what I got. I don’t think any dosing routine should be promoted over another, I think you should choose a routine that works for you and your tank, period. Trial and error is the only thing we should all agree on 👍🏻
 
Then came Tom Barr with his Estimated Index idea and said, "forget that".
This was in the mid 1990's, about 30 years ago.

Few would argue that since then the debate on fertilisation has settled, just take the excitement around toxicity or lean dosing as examples. But as far as I can tell from following these discussions I am not sure how much of this has crystallised in new methods that have proven their unique value and could achieve what couldn't be achieved without them. Yes, some prefer to dose the water column, others prefer a leaner column and let the substrate do the magic. Some of the most opinionated in these debates never show their plants doing the talking on a forum or in competition, while on the opposite side some of the best scapers are of the opinion that ferts are not the first to look into for root causes of success or failure.

So my follow up question is:

Since EI and ADA style fertilisation approaches were invented 3 decades ago, and looking beyond marketing and branding, what are the innovations in fertilisation that have so clearly demonstrated new features and value for them to stick and claim a chapter in the history books of planted tanks?
 
I don't follow what your point is.
Well, this thread was started with the question "Are we past the Estimative Index way of dosing?". Then, if so, my follow up question is what is it in that case that came after?

As much as I enjoy the debates, frankly I have not seen much progress other than that we are tweaking the 2 or 3 initial concepts. I have settled on watered down version of EI, and ferts is the least of my concerns. Why it is one of the most hotly debated issues in our hobby is not entirely clear to me, as it seems we know what to do to get it right, nor do I see that the state of the art today is much different from what we had 1 or even 2 decades ago. When it is about ferts, sometimes it seems to me we debate solutions looking for a problem. But this is my personal observation, and I may be wrong here - hence my follow up question.
 
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There’s a term in video gaming called “min maxing”. And I believe this is where we are for the methods you mention. This is most obvious with EI dosing. As we tweak our numbers, down or up, eliminate waste and fine tune to bring peak plant health, we are essentially min maxing the process . This can get a bit tricky as each tank responds differently, but that’s the beauty of EI.

Maybe there’s min maxing in Aqua Soil production, but I’m not familiar enough to say. But with different versions of branded Aqua Soils coming out, maybe this is the case?
 
I don't think I've ever dosed sufficient fertz for it to be considered true EI. And I've always used all in one ready mixed products like TNC Complete. Instead I watch my plants closely for signs of deficiency and just up the entire dose when I feel it's necessary, or add TNC Lite if I think it's a K deficiency etc. Not very sophisticated, but it works for me and I'm not really interested in the minutia of fertz dosing.

From a point of view of advising newbies I think EI is probably a good place to start. It's tried and tested and is fairly simple to master, leaving those new to the hobby to concentrate on more difficult aspects, like getting the CO2 right. EI can always be tailored later so the nutrient load isn't so excessive. The necessary water changes perhaps help to establish good husbandry and maintenance habits. I guess it all contributes to initial success and hobbyist retention.

I'm pretty sure excess nutrients don't cause algae in a well balanced system. But if something is out of kilter then I suspect it can sometimes exacerbate existing problems.

Back in the day I kept low-energy dirt tanks and didn't dose the water column. Aside from nutrients contributed by fish food and organic waste, most were locked up in the substrate. This allowed me to use relatively high light intensity and a 12hr or so photoperiod, without encouraging too much algae. I might well go back to doing things that way and dose a lot leaner.
 
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