Who doses potassium?

[Randy Holmes-Farley]

I did my first Triton test and they said I was low potassium, everything else was in order. I use the 4 part Triton method via dosser. I started to dos brightwell Chetogro based on element list of product. I figured my cheto was pulling out all my potassium. I been dosing 15 ml once a week in my 120 gallon.

Element list of brightwell cheto grow.
"Potassium - Protein synthesis, water and charge balance, enzyme activation.
Boron - Chlorophyll production, flowering, root growth, cell function.
Carbon - Required for all organic compounds.
Calcium - Cell wall stability and permeability, enzyme activation, cell response to stimuli.
Chlorine - Water and charge balance, photosynthesis.
Iron - Required for photosynthesis, component of enzymes utilized in redox reactions.
Magnesium - Component of chlorophyll, enzyme activation.
Manganese - Formation of amino acids, enzyme activation.
Molybdenum and Cobalt - Required for nitrate reduction.
Nickel - Enzyme activation, processing of nitrogenous material.
Sulfur - Component of proteins and the coenzymes that are involved with nutrient utilization and growth.
Zinc - Chlorophyll production, enzyme activation."

there’s really no obvious reason that organism growth necessarily reduces potassium. When you add foods you should be adding the potassium in those foods, same as they took up when growing.

If you feed potassium deficient foods, k may certainly decline. Dosing inorganic nutrients may also promote the decline.

but the biggest cause of a K drop may be use if a two part that lacks sufficient potassium to offset the salinity rise and correction effects.

 

[sayurasem]

there’s really no obvious reason that organism growth necessarily reduces potassium. When you add foods you should be adding the potassium in those foods, same as they took up when growing.

If you feed potassium deficient foods, k may certainly decline. Dosing inorganic nutrients may also promote the decline.

but the biggest cause of a K drop may be use if a two part that lacks sufficient potassium to offset the salinity rise and correction effects.

Hi Randy, could you elaborate on adding potassium to food? May I ask examples of potassium deficient foods? Also what is considered inorganic nutrients?

I’m having issues with my montiporas, mainly capricornis and palawensis. Capricornis are turning pale lighter color and palawensis turning brown. Digitatas and encrusting montis looks normal.

I use salifert to test potassium and it was off the chart (literally). It took 30 drops of reagent k3 to get my water sample blue. Assuming salifert potassium test kit chart is gradual, my potassium would be 200ppm.

 

[Randy Holmes-Farley]

I’d try the kit on some new salt water, and/or get an icp test before raising it thst much.

Inorganic nutrients in the context of this discussion means nitrate or ammonia, and phosphate.

I do not know what foods may be potassium [edited to correct a typo from phosphate] deficient, but I have a hypothesis that frozen foods that are rinsed may be.

 

[sayurasem]

I’d try the kit on some new salt water, and/or get an icp test before raising it thst much.

Inorganic nutrients in the context of this discussion means nitrate or ammonia, and phosphate.

I do not know what foods may be phosphate deficient, but I have a hypothesis that frozen foods that are rinsed may be.

Thank you for your reply. I tested new freshly mixed saltwater at 35ppt and tested the same. 30 drops equal to 200ppm potassium. I don’t have access to icp test but I will get one.

I just wanted to make sure, did you mean potassium or phosphate deficient?

 

[Randy Holmes-Farley]

Thank you for your reply. I tested new freshly mixed saltwater at 35ppt and tested the same. 30 drops equal to 200ppm potassium. I don’t have access to icp test but I will get one.

I just wanted to make sure, did you mean potassium or phosphate deficient?

I dont know what comment of mine you are asking about, but if quality new salt water tests 200 ppm potassium like your tank, it is most likely a testing issue, not a low potassium issue.

 

[sayurasem]

there’s really no obvious reason that organism growth necessarily reduces potassium. When you add foods you should be adding the potassium in those foods, same as they took up when growing.

If you feed potassium deficient foods, k may certainly decline. Dosing inorganic nutrients may also promote the decline.

but the biggest cause of a K drop may be use if a two part that lacks sufficient potassium to offset the salinity rise and correction effects.

I dont know what comment of mine you are asking about, but if quality new salt water tests 200 ppm potassium like your tank, it is most likely a testing issue, not a low potassium issue.

You mentioned “if you feed potassium deficient foods, k may certainly decline.” I asked what kind of food that are potassium deficient, but you reply with phosphate deficient food.

I’d try the kit on some new salt water, and/or get an icp test before raising it thst much.

Inorganic nutrients in the context of this discussion means nitrate or ammonia, and phosphate.

I do not know what foods may be phosphate deficient, but I have a hypothesis that frozen foods that are rinsed may be.

 

[Randy Holmes-Farley]

You mentioned “if you feed potassium deficient foods, k may certainly decline.” I asked what kind of food that are potassium deficient, but you reply with phosphate deficient food.

Sorry, phosphate was a typo. It should read potassium and I corrected it.

 

[sayurasem]

Sorry, phosphate was a typo. It should read potassium and I corrected it.

Ahh gotcha. Thank you

 

[serwobow]

there’s really no obvious reason that organism growth necessarily reduces potassium. When you add foods you should be adding the potassium in those foods, same as they took up when growing.

If you feed potassium deficient foods, k may certainly decline. Dosing inorganic nutrients may also promote the decline.

but the biggest cause of a K drop may be use if a two part that lacks sufficient potassium to offset the salinity rise and correction effects.

If you are removing organisms like chaeto or cyano from the tank, it seems like potassium could definitely deplete in the tank, since organisms actively take up potassium. The concentration of potassium inside a cell is in the range of 6000ppm. If you are removing alot of chaeto or other organism, it seems like that could deplete potassium. Feeding may replace that potassium, or not, as you said above.

 

[Randy Holmes-Farley]

If you are removing organisms like chaeto or cyano from the tank, it seems like potassium could definitely deplete in the tank, since organisms actively take up potassium. The concentration of potassium inside a cell is in the range of 6000ppm. If you are removing alot of chaeto or other organism, it seems like that could deplete potassium. Feeding may replace that potassium, or not, as you said above.

Yes, and no.

True, those organisms certainly take up potassium and remove it.

But if the N and P to make that new tissue comes from other, fed, tissues (e.g., fish food), then those additions bring in potassium, and for K to deplete requires that the tissues used as food have relatively less K per N and P, than do the organisms being exported. Why would that necessarily be true? Maybe because K is lost from burst cells in freezing and drying of foods, and using whole, fresh foods may reduce or eliminate that issue.

As an a priori argument, one might think that accumulating potassium might be just as common as depleting potassium, if whole, fresh foods make up the sources of all N and P in the tank. In fact, accumulation might be more common than depletion since some dissolved N and P that might otherwise get into organisms is exported by skimmers, GAC, etc, and hence the amount of tissue added in the tank would be a bit less than was fed.

Of course, if one is dosing N and P (other than foods), then there certainly may be a tendency to export K.

 

[serwobow]

Your a priori argument seems logical (that K should accumulate over time in many tanks) but its not like people are commonly reporting high K issues in their triton tests. Low K seems more common. Maybe because a substantial fraction of people currently keeping reef tanks are dosing N and/or P, and thus there is a net K depletion over time? I dose NO3, at about 5ppm per day to maintain about 30ppm, but P stays constant with constant feeding (about 10ppb), and K depletes, according to my test kits (maybe depleting 1ppm/day or thereabouts), so I re-boost it up every couple months with KCl. Since every organism in the tank will take up K,N, and P at a different rate, it is unlikely that any food is going match up just right with the depletion rates.

 

[Randy Holmes-Farley]

Your a priori argument seems logical (that K should accumulate over time in many tanks) but its not like people are commonly reporting high K issues in their triton tests. Low K seems more common. Maybe because a substantial fraction of people currently keeping reef tanks are dosing N and/or P, and thus there is a net K depletion over time? I dose NO3, at about 5ppm per day to maintain about 30ppm, but P stays constant with constant feeding (about 10ppb), and K depletes, according to my test kits (maybe depleting 1ppm/day or thereabouts), so I re-boost it up every couple months with KCl. Since every organism in the tank will take up K,N, and P at a different rate, it is unlikely that any food is going match up just right with the depletion rates.

I don't think enough people dose N and P to fully explain it, but IMO, fish food processing may well do so. Since most K is internal to cells, and not tightly bound, breaking open cells may cause it to be released during steps relating to water removal by filtering.

Cooking foods in water, for example reduces potassium:

https://doi.org/10.1111/jhn.12846

"Cooking in water, pressure cooking and cooking in a microwave oven reduced potassium levels in all food groups, particularly in cereals and derivatives, fruits and derivatives, meats and derivatives, legumes, and leafy and cruciferous vegetables. "