Potassium Depletion

[xaflatoonx]

Tank size - 300G water volume.
Mixed reef - predominantly SPS. Mainly 2-3 big colonies of SPS - with others growing.

I do regular ICP tests - (monthly) and weekly home tests.

My potassium was 360 in one of the first ICP tests i did.
Since then - i have been dosing potassium to get it back up.
I dose 50ML of potassium a day.

Is that normal?

My Alk consumption is 130ml a day to keep it at 7.8dkh stable.
My Cal consumption is 200ml a day to keep it at 390ppm. Although i am trying to raise that to get to 450.
My mag consumption is 40 ml a day to keep it at 1300 stable.

I run a salifert test to check all big three, plus Nitrate, Phosphate and Potassium every week.
My nitrates are around 25 and phose at 0.12.

So - getting back to my question.
My salifert test kit says my potassium is now 390. Every ICP test i have ran confirms what i see in the salifert reading. I have increased it from 360 gradually over the last 4 weeks. i dose 50 ml A DAY to keep it at 390 and every now and then i dose a little more to hopefully bring it up to 410 which is my goal.

Why is my potassium consumption so high?
Is that even possible?


every one i have talked to says something is wrong. and that it cant be. I am reading the same.

 

[xaflatoonx]

bump

 

[xaflatoonx]

@Randy Holmes-Farley - sorry to tag you particularly - but really want your thoughts on this

 

[xaflatoonx]

@revhtree - can you help move the thread to Reef Chemistry please. Maybe its in the wrong section

 

[Deep]

50 ml of Potassium at what concentration ?
if you know that then you will be able to find out how much that 50 ml will raise Potassium levels for your water volume. So do you know the concentration ?

 

[Useful_Idiot]

I had the same problem. Using 2 part at 100 ml each per day and skimping on water changes, my sps would stress. Big WC's would bring them back. Started testing K and found it was getting down to 350 ish. I was making stock solution from the bright well powder and adding 500 ml a week.
I started using Tropic Marin part c and Red Sea colors trace elements and no longer need to dose K. Probably more due to the part C.
Needle wheel skimmers combined with carbon dosing reduce K, but I don't know how.

 

[xaflatoonx]

Good question - and sorry for the detail miss.

I am using the brightwell aquatics potassion-P suppliment
I put 100 Grams of that powder into a 1 liter bottle.

supposedly that solution would raise 1 mg/l by dosing 23.18ml of solution.

50 ml of Potassium at what concentration ?
if you know that then you will be able to find out how much that 50 ml will raise Potassium levels for your water volume. So do you know the concentration ?

 

[xaflatoonx]

I had the same problem. Using 2 part at 100 ml each per day and skimping on water changes, my sps would stress. Big WC's would bring them back. Started testing K and found it was getting down to 350 ish. I was making stock solution from the bright well powder and adding 500 ml a week.
I started using Tropic Marin part c and Red Sea colors trace elements and no longer need to dose K. Probably more due to the part C.
Needle wheel skimmers combined with carbon dosing reduce K, but I don't know how.

appreciate the insight bud.

So i dont do water changes - and dosing elements as per the ICP tests.
still though - depletion of Potassium like mine - is not something i have read anywhere about - nor others in my town on the same program are experiencing.

 

[Randy Holmes-Farley]

Potassium sometimes becomes depleted, but there is no a priori reason it should unless you are dosing a lot of inorganic nitrate or amino acids.

IMO, the potassium level is a net balance between what comes in with foods and what is incorporated into growing tissue (including bacteria). Essentially tissue with potassium in it added as foods, and tissue with potassium in it created in the tank.

In my tank it did not deplete after 20 years. I did 1% daily water changes, but such changes limit a decline (or a rise), but really don't hold it against substantial depletion pressure.

I suspect (but have no experimental evidence) that rinsing foods before use may be a contributor to depleting potassium, especially if they have been frozen or cooked in a way that breaks open cell membranes, since potassium is largely held inside of cells.

 

[xaflatoonx]

i feed using the Red Sea AB+ coral food - which is aminos i believe.
Maybe thats decreasing my Potassium then?

i dost 50ml every other day - or every three days.

 

[Randy Holmes-Farley]

i feed using the Red Sea AB+ coral food - which is aminos i believe.
Maybe thats decreasing my Potassium then?

i dost 50ml every other day - or every three days.

No fish food?

Yes, dosing any form of pure N and P additives that do not contain potassium can cause a slow depletion of potassium.

 

[xaflatoonx]

i definitely do fish food as well.

i feed frozen once or twice a day. And pellets twice a day.
i know i over feed - i feel like it keeps their immunity up.

but i have a good skimmer and a huge fuge so i try to balance my nutrients that way.

thanks so much for being responsive by the way - i appreciate your input.