Potassium question

[Panicked Reefer]

It would appear my tank is using a tremendous amount of potassium. I used the red sea kit to measure and did not get a reading with the .5ml of reagent on NOV 20rd. I dosed 100ml of the res sea potassium supplement on this day. Retested 3 days later on NOV 23 and was showing 386. 7 days later on NOV 30th I tested and was unable to get a reading using the full .5ml of reagent. Both times I did not get a color change I re tested so I'm fairly confident it was blow the measurable amount on the red sea test. The other trace elements I was able to test for tested low. Added the amount red sea recommend and then retested on the 23rd. All increased as expected. Starting the 23rd I have dosed 30ml of cheato gro 2x a week. Everything as per the test kit has maintained except the potassium. It is below the tests capabilities. I picked up some potassium chloride and found a spreadsheet that suggests 50g of potassium chloride in 1000ml of RODI. I am unclear on how much I should dose at this ratio. In searching I have found a website that Randy suggests and to multiply the amout by .74 to compensate for the difference in potassium chloride and potassium nitrate. I am coming up with the full 1000ml would raise my 120g by only 37ppm. Does this sound correct? If so what would the suggested starting dose be?

 

[Randy Holmes-Farley]

I suspect a test problem, not a low value. Try the test on some new salt water.