Imagine a hydroponic setup like this:



Where nutrient solution of N-P-K is added via gray funnel to the tank. The roots are in an open-top beaker that is suspended in the tub below the water line. Nutrients are taken out of solution by the roots at the bottom of the black beaker and are periodically added to the entire water tub by the gray funnel.

Will the nutrients in the entire tank always try to evenly distribute in the beaker? For instance, if the plant is taking up N but not P or K, will the lower distribution of N inside that beaker cause N (and only N) from the tub outside the beaker to flow into the beaker?

Or will all 3 of N-P-K will flow from the tub into the beaker, and it doesn't matter that the plant only removed the N?

P and K will diffuse and reach close to equilibrium and then slow down / nearly stop as diffusion is asymptotic. N will continue to move towards equilibrium as the plant removes N from the system.

Depending on how much N is removed by the plant, and how much of a gap there is between the smaller cup thingamajig and the larger tank, and the size of each cup/tank, it might or might not be an appreciable difference.

Stuff being removed from systems is kind of fun to think about. Maybe someone will supply some equations.

But this difference would approach zero if the plant were to stop uptaking N for some period of time? Would having a small pump at the bottom of the larger tank to basically constantly mix the large tub decrease the time it takes for the nutrients to equalize? And the larger the difference between N in the cup to N in the tank, the faster N would move from the tank to the cup?

Yes, yes and yes.

Think of the N as food coloring and the plant as a magic food coloring remover

And the same applies for molecules in the air? So a plastic baggie with a small hole that had a co2 remover inside of it would constantly be "sucking" co2 into the baggie from the outside air until the amount of co2 inside the bag reached the amount of co2 outside the bag?

Yes. It would be moving towards equilibrium asymptotically between outside the bag and inside and the CO2 remover would keep it from approaching equilibrium.

The plant is alive and to treat the whole system as inorganic will only at the edges display results. This is to say that organic activity is not a function of the inorganic.

This can be studied by taking measurements over time but not by inorganic thought.

A similar approach is seen in biochemical/science books when the passage of fluids across a cellular membrane, in vivo, is treated passively or high concentration vis a vis low concentration.
The F=MA approach is used over a broad membrane but it is forgotten that the movements and activities are within life.

Laying the cause to the concentrations on the fluids themselves is similar to stating that in a waterfall the weight of the water above is pushing the lower water to the ground.

Start out with a large number of pennies all lying heads up. Then randomly pick pennies and turn them over one at a time. Eventually you will end up with about half heads up and half tails up.


PairTheBoard

Treating the plant as a mechanical NPK destroyer is enough for me and answers all my questions. Also, when you take LSD you trip balls. If you get a lobotomy on certain parts of your brain, we know how this will affect your behavior. Those two facts alone should clear up any confusions you have about organic activity being a function of the inorganic.

My point is that scientifically speaking, the values must be measured. The plant shouldn't be considered as a nutrient eater of steady state or any type of state unless measurements somehow reveal its absorptive nature.

Sensors can be placed within the fluid which will give an indication of the absorptive nature of the plant in time. The mathematics of this activity can project the quantitative amounts of nutrition the plant absorbs and relate it to the measurements of fluid concentrations. This of course is related to the input of nutrients which in the most calculable form would be steady state .

It doesn't end here as the activity of the plant , in consideration, won't necessarily be a function of the concentrations but as the situation is not a closed system there are the extratelluric matters of the cosmic movements such as the sun and moon, the seasons, and for certain day and night.

It would be interesting to see how the plant takes in nutrition throughout the day split into nocturnal and daylight periods, as as I said, seasons of the year .

The point being that if only concentrations are desired a suction motor could replace the plant and then a mechanistic approach might be facilitated.

Otherwise, with the plant within the system, to assume a plant activity of a predisposed theory would be a source of error.

It should depend on the use case, shouldn't it? I'm not a student in a chem lab, i'm a hydroponic home-gamer growing peppers in my living room.

I have a DWC setup but some species are getting huge, and I'm wanting to restrict the roots of a scotch bonnet seedling to see if I can encourage it to grow almost like a bonsai, but I don't want to be constantly re-filling a small container with hydroponic fluid, I'd like to just set the container inside a bigger container, and I just wanted to know if the smaller cup inside the big tub would run out of nutrients and the plant would starve, or if the nutrients would diffuse into the smaller cup from the larger tub over time.

I bow to your knowledge here that you should ask a question of real life; what's this place coming to ?

As to the diffusion of nutrients the plant is the active agent here and so long as there is a open road to feeding it should work. But still, the roots may need some space and if congested it would seem to affect growth. I guess this is the way a bonsai tree is produced, by congesting the roots .

I sure would like to hear what happens and by the way will these hot peppers become very small and even more hot ? Please do it and give us a taste test of these mini peppers. lol

The best to you; I would like to know what happens . Thank you.

will do, thanks for the info