Potassium Sulfate

[Bri Guy]

We recently had a reef meeting at a University Lab (Thankx again KevChem) and I was able to get a K test done, and mine is low at about 260ppm, I was wondering if it would be ok to boost my K by about 140ppm with K₂SO₄ ?

Or would that add too much sulfate?

Heres the thread that covers the testing and what we knew about the sulfate...
http://www.reefcentral.com/forums/showthread.php?s=&threadid=1554183

thankx in advance

[bertoni]

That would raise sulfate around 480 ppm, and the normal level of sulfate is around 2700 ppm. I'd use something else, personally, but it might be fine.

[Randy Holmes-Farley]

Where did you find potassium sulfate and do you know anything about its purity? If pure enough, it may be OK, but potassium chloride would cause less ionic changes.

[Randy Holmes-Farley]

FWIW, I made the following post on that thread that you linked:

Most salt mixes are substantially deficient in K+ and, at best, even the top of the line salt mixes have discrepencies between what they post their salt mix contains versus what many of us get for readings when we test with various kits.


Someone posted this thread in the Reef Chemistry forum, so I just thought I post one comment. yes, there is a big discrepancy between what many salt manufacturers say they put in and what folks get with test kits. IMO, that leaves open the question as to which one is not true. I am not at present prepared to say that nearly every salt mix manufacturer is lying about what they put in, and am equally worried about test kit accuracy.

FWIW, a number of years ago when Craig Bingman tested salt mixes with high end techniques, he found about NSW levels in them, not the very low levels that the kits now show. In the meantime there have been a few salt studies that give odd (and obviously incorrect) results for many ions, leaving us really not having much confidence in potassium test results.

[Bri Guy]

The potassuim sulfate if from FW planted fertilizer.

Thankx for the tips, ill keep my eye out for some KCl, id rather be safe than sorry.

[Randy Holmes-Farley]

You're welcome.

Good luck. :)