K uptake rate

Tom Barr

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Re: K uptake rate

Pretty variable.

1.Plant species dependency
2. Concentration dependence
3. Lots of luxury uptake
4. Highly mobile thus allows for the translocation
5. Genetic adaptation to various concentrations

Generally, using the NO3 as proxy for estimation based on demand seems to be a useful method.

Most aquatic plants tend to have about a 1:1 ratio of N: K.
But.....that does not imply that is optimal for growth, it's certainly way beyond limiting levels of K+ which is roughly a factor 4x less.


So an uptake of 1-4ppm a day might be generous, but the actual limiting levels are 4x less, so 0.25-1ppm is likely not limiting for most plants.

Regards,
Tom Barr
 

Left C

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Sep 26, 2005
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Re: K uptake rate

Thanks a bunch Mr. Barr!!!! I am currently dosing K2SO4 at the same rate as KNO3. I thought that it may be a little high but I'm not seeing any problems like Mg uptake or anything.
 

Tom Barr

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Re: K uptake rate

I doubt you would see any issues as long as things do not get limiting for K+.

I wrote a post to the effect that using KNO3 as a sole source of K+ is adequate, adding K2SO4 will not hurt though and can be useful in some cases where the tap has high NO3, or the tank has a high fish load and lower light.

We add K2SO4 from GH boosters as rule anyhow, so no need to add even more.


Regards,
Tom Barr