This article is designed to give a back ground on various dosing routines from the past and present.

Some of the older semi complete fertilizer routines are PMDD(about 1995-1996):

Practical PMDD Information -

In this recipe, the goal is using test kits to monitor NO3, Fe(as a proxy for all the other traces) and PO4 to mee the demands of the plants.

This assumed(incorrectly as it was later shown/proven) that limiting NO3 and PO4 would reduce algae and provide good health for plants(this latter part is true however).

The fertilizers are added to water and dosed by milliiliters.
This provides higher accuracy than teaspoons but the original recipe is measured with teaspoons and tablespoons.
However, anyone might use a gram scale accurate to 0.01 to 0.001 grams if they so chose.

But are they gaining anything from this increased accuracy as far as the plants are concerned?

No one has ever shown this to be the case. That's good also, plants are pretty flexible and can grow over a wide range well.

Also noted is the infinite series dilution factors to help re set a tank that gets too far outside a particular range of ppms.

Thus testing is the key here and water changes are done to keep things balanced if the dosing and tweaking for each tank is neglected.
Some other methods have co opted this and claimed it as their own original idea and concpet.

From this method, evolved the list of levels and parameters(1997, see, the first local aquatic plant club in the USA and now the largest).

References -

This was the first time it was suggested to add PO4 as a fertilizer to help plant growth. That radically changed fertilization routines. It also increased uptake of CO2, NO3 and K.

Steve Dixon had a profound influence on me and this article.
He is still the wisest and smartest person I've met in this hobby.
We all owe a lot of gratitude to him.

You'll note I suggest several accuracy and qualitity levels of test kits and rechecking the readings to be sure they are correct versus a reference. You'll also note a rather high level of traces I was adding to rule out any limitation there. One thing many assume I did not do much of, or rather, I am not really known for is suggesting testing and ranges or targets folks might want to try and aim for.

I still suggest water changes. We discussed not doing water changes and simply monitoring the test readings instead. 3 members tried this and each reported a better level of plant health and tank health, especially with higher fish loading than without water changes. This is not right/wrong, black or white, it's more of what does better vs a tradeoff. No water changes can be done. I've never stated otherwise in the past:cool:

I ran into issues heping people with no access to test kits in third world countries and folks that are just honest enough to say they will not test, or are too cheap to buy the good test kits that are accurate, or lack the skills or motivation to claibrate them.

I was cheap, I was lazy, so I looked for a simple solution to get around testing. I'd always done large water changes. I like fish and they always are healthier with large weekly or 2x a week 50% water changes.
Ask any Discus breeder.

So using that habit which most anyone can do with a pair of hoses(I laugh at silly folks that use buckets) to drain and fill, see Python automatic water changers or a DIY set ups........I used the dilution factor with a 50% weekly water change to target and estimate a range or index and developed EI.

Many folks where not ready to abandon test kits however.
They had been engrained to believe and place all their faith in them by every book, magazine and article.

But the data is only as good as the person taking the measurement and only as good as the test kit and it's accuracy!!!!!!!!!!!!!!!!!!!!!

The test kit makes assumptions(that it's accurate, many are not!!).
So do we.

The link to EI is here:

The full version:

Some errors and misunderstandings often occur: it's not written in stone, 50% weekly water changes, nor the levels added, account for fish loads, account for tap water with NO3/PO4 etc. You may not need to add as much and still get the same results.

Hate water changes and like low mainteance slow growth?

Here's yet another solution to non CO2 methods and some arguments why this method is very good for our human habits and tanks:

Given that many folks have killed fish using CO2 gas, I still have not met nor heard of any substantiated cases of PO4 or NO3 poisoning using KNO3 etc, I often onder how some can carry on and on about bad levels of NO3, PO4 etc and miss the fact that they "pollute" their tanks with CO2 gas to the point of killing their fish or stressing them out.

Clearly when used correctly, CO2 does not pollute their tank..........but nor does KNO3.........but some enjoy using such flawed logic in their arguements.

When I've called folks out on that, I'm a bad guy.
I guess I am expected to say only nice furry things:rolleyes:

Still, more folks have killed fish using CO2 gas than any other parameter. And it's meaurement is wrought with errors and assumptions.

Myself and Vaughn, Gomer and others have sought to rectify this.

Even more disturbing is the lack of light meaurement and testing that is never done in this hobby.

I think I may be one of the very few people using a PAR light meter to measure specifically my light intensities.

So for all the banter the "You should be testing" crowd rattles on about, I've never met yet that's tested their light in plant useful units in their tanks.

Sort of ironic ain't it?

Still, there are critical things like not adding too much light, adding enough CO2 with decent surface current, but the nutrients only play a fraction of the role here, folks place wayyy too much importance and try to draw correlations between their successes and never bother to critical assess things like light or CO2.

You'd be best served focusing more on CO2 and adpoting most any dosing method. Plants all have the same needs and the rates of growth may vary depending on light, CO2 and limitations

In order to really know what is occuring however, you need to have command of CO2 and the test kit methods, few do and even fewer are willing to test a control tank to see if their hypothesis is correct or not.

You can add Excel in here as well as an alternative slower growth method as well. Roughly assume 1/3 EI dosing using this. Even less with higher fish loads.

Excel is a poison at higher levels as well, but not one single hobbyist has ever even bothered to test this either :rolleyes:

But that does not include myself..............I have a test method, actually several methods to do so.

Question things and see if your baloney meter and snake oil detector goes off based on their responses.

That is a good idea. Ask them if they have tested their hypothesis when they state things as fact, ask them how the set up the test etc.

Then decide.
Then test it yourself and see.

Then you'll know.

I suggest that folks try each method that's out there.
Non CO2 and a CO2 enriched method.
High light and low light.
Lean vs rich, mess with CO2 levels.
Commericial vs DIY.

Light routines?

CO2 routines?

You should give these due consideration prior to choosing a nutrient routine!
It can make your life 100% easier and the hobby much more enjoyable.

Less light= less work, more stable systems

So do not run out and get a high light set up, try lower light values, this will still help when used with CO2 and some dosing.

Clearly you do not need a lot of dosing if the light is low also, so if that is goal(less), then use less light to match.

Sediment routines are becoming more common than in the past.
This is perhaps rediscovering what many used 30 or more years ago.
CO2 helped many to grow aquatic plants well and aquarist went with inert sand and dosed the water column for some time. Dupla suggested the CO2 and inert sand with some laterite.
So this was marketing driven really.

Some aquarist did not allow the sediments to mature or did enough water changes in the initial phase. Variations on recipes also varied widely for nutrient rich sediment, as well as fear and myths about anaerobic sediments and PO4, NO3 etc.

Many tried soils but when uprooting, often made a mess due to not being careful.
Changes to trimming(mostly going to topping instead of uprooting) helped this problem.

ADA had a rich sediment product and this marketing helped increase interest in sediments once again. ADA still added fets to the water column , however, fairly low in concentration. This helped placate the fear and myth dogma that is still in place in the hobby about nutrients and the water column, but.........still has a source of nutrients for plants/roots.

Still, whether the aquarist believes nutrients to be the Root of all Evil or not, adding enriched sediments tends to be a good idea overall, no matter which approach you chose, unless you move plants around all the time and do not want to bothered with being careful.

So this works whether you use water column ferts, or not..........CO2, Excel, or no Carbon enrichment of any sort.

It adds a back up supply if you forget to dose the water column, or leave for a few days on a vacation. Water column fertilizers increase the life span of of the sediments by reducing demand. Reducing light also increases the life span and the ability to maintain even lower residual levels of nutrients if that is your goal. It should be noted however, adding enriched sediment still adds plenty of nutrients, you just will not measure a high residual in the water column, the total nutrients is still much higher however.

Many show test(ADA did this quite unfairly) with plain sand vs their enriched sediment and show the growth differences. Of course you will see huge dramatic differences, one has nutrients, the other has none.............

It's like comparing CO2 enrichment vs no CO2, the difference is huge.
To be fair, you would want to show a several types of sediments with different concentrations of nutrients, % organic matter and particle size.

You could show an upper range, some modified hoagland's solution, then DI water and plain sand, plant the plants in hydroponic culture(99% of the aquatic plants will adapt and do well, most are amphibious), as this will make CO2 independent and non limiting. All the sediments will fall somewhere in between these two controls(non limiting and strongly limiting).

This is an easy simple way to measure the effectiveness of a sediment on aquatic plant growth without any dependency from CO2, water column nutrients or light(assuming all plants are exposed to the same PAR and duration).

Tom Barr