Nutreint uptake blocking

Henry Hatch

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Aug 31, 2006
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I have read from time to time that an excess of one nutrient can block uptake of another. Is there any truth to this ?

Henry
 

Tom Barr

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Jan 23, 2005
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No, not at the levels we typically use.
It' occurs at very high levels/concentrations.

Everytime some one makes this claim, I have an example or a case where it is falsified.

Adding more of a nutrient you thought you have enough of, but really where limited by, causes this myth to be promoted and the person is convinced of it. They do not try and set up a specific test to see and they also have no control to even compare it to.

If you relieve a limitation say P, it can cause a dramatic increase in the demand of say CO2, or N. So while you where not limited by N or CO2 prior, now you are.

This will lead you to think that high P= algae.
But that is incorrect.

Other cases where CO2 becomes limiting in certain species expresses itself as stunted or smaller tips. Many assume Ca for some reason, but CO2 can be doing fine, then you add K+ to a limited system and the increase now shifts the uptake and causes CO2 to be limiting(or N or P etc).

Regards,
Tom Barr
 

Henry Hatch

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Aug 31, 2006
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You hit on a point that I've been thinking about as I progress in the hobby. Instead of thinking in terms of what I need to add or delete to solve a nutritional problem one needs to think about a system consisting of light, co2, and ferts. It's not one thing, it's all three working together, or not. Correlation is not causation.

I think that is the key to EI dosing. Eliminate limiting factors.
 

Tom Barr

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EI just eliminates part of the issue.
Same with most fert routines if you follow them.
The other parts are CO2 and light.

But.....

There's a 4th part as well.
Rather obvious, but very often over looked.

Basic aquarium mainteance, things like cleaning the filter, water changes, cleaning glass, running a diatom filter if there's algae or muck in the water after you redo something or do a large change. Good current, adequate filtration, wise fish loads, good algae eating crew..........

Basic stuff, but I do not k now how many times folks have claimed they are doing everything right, then I go over to their home and there's virtually no filtration, tubes are clogged, media has not been cleaned of changed in months etc.

and they say it's my fault that EI does not work for them:rolleyes:

Ya huh.............

You need to be careful in ascribing what/who to blame when it comes to algae, the tank, etc.

It's not a single variable system.
I have no idea why so many assume it is.
There's no one silver bullet.

Older folks that have experience know this, but the folks with a little knowledge to be dangerous, but not enough to put it all together are often the problem.

They think they figured it out and cannot see all the parts yet.
So they claim false evidence and draw poor conclusions.

I mentioned the errors in the logic, they think they are right, so poo poo me, it's easier than admitting bad logic(at least to one's ego, not in solving the issue).

If I had nickel for every time that one happened I'd be rich:)

When you approach these questions, think about how you could reduce things down and isolate one variable. Providing non limiting nutrients will rule, them out.
Light?

Well you can use commonly used real low light and real high light and then some in between. That will cover most of the tanks folks deal with.

Measure with a light meter is useful, but not needed. Light, unlike nutrients and CO2, is very stable over the 3-8 week test periods typically.

So you can assume it's stable.

That leaves our good friend, CO2.

You will see me moving more and more towards it over the years as a primary test focus.

Along the way, I've found some new ideas and methods.
Much more than we knew prior.
And there's still yet more to come.


Regards,
Tom Barr