Hi all,
I a discussion over on a reef forum about GFO, Granular FerricOxide, phosphate binding media a few people pointed out that the GFOs dont bind the fosfate they only store it in an equilibrium state with the surrounding water.
As Randy-Holmes Farley explains:
So, if I where to take a high concentration solution of phosphate and dip the GFO media in until it's saturated and the place it in a planted tank the GFO media would slowly release fosfate into the water column. I am sure that calculations can be made to achieve a specific level of fostfate.
This has quite a few possibilites, dosing PO4 once a week or month even, the GFO will absorb the dosed PO4 and release it slowly into the water column. Gone are the need for dosing pumps and physics will do the job. We can maintain an exact level of PO4, even without measuring, for longer periods of time.
I havent found an equilibrium based NO3 binding media yet but I'm sure there has to be one. If there is one for NO3 and one for K I'd say binding media could be utilised as a complete regimen for dosing macro.
What do you all think?
cheers
Mattias
I a discussion over on a reef forum about GFO, Granular FerricOxide, phosphate binding media a few people pointed out that the GFOs dont bind the fosfate they only store it in an equilibrium state with the surrounding water.
As Randy-Holmes Farley explains:
Phosphate bound to GFO surfaces is still available to the water column by exchange, so the sequestering is temporary rather than permanent. This fact is known in the literature, and can be shown experimentally. I will show the detail in upcoming articles, but it can easily be demonstrated by adsorbing phosphate onto GFO, and adding enough so that a detectable concentration of phosphate (say, 0.1 to 1 ppm) is in equilibrium with the solids. Then remove the solid GFO and add it to seawater with no detectable phosphate. The now-detectable phosphate in the new seawater shows that the phosphate can be released from the GFO media when the aquarium's phosphate concentration drops low enough.
So, if I where to take a high concentration solution of phosphate and dip the GFO media in until it's saturated and the place it in a planted tank the GFO media would slowly release fosfate into the water column. I am sure that calculations can be made to achieve a specific level of fostfate.
This has quite a few possibilites, dosing PO4 once a week or month even, the GFO will absorb the dosed PO4 and release it slowly into the water column. Gone are the need for dosing pumps and physics will do the job. We can maintain an exact level of PO4, even without measuring, for longer periods of time.
I havent found an equilibrium based NO3 binding media yet but I'm sure there has to be one. If there is one for NO3 and one for K I'd say binding media could be utilised as a complete regimen for dosing macro.
What do you all think?
cheers
Mattias