KCl Supplement

3FeetReef · Feb 11, 2017

Hi,

I had a friend of mine test my potassium levels for me and they turned out to be 300 ppm. He checked my test kit using a 400 ppm standard he made from a 1000 ppm KCl reference solution and the kit turned out to be dead on. Knowing this, I want to add some sort of potassium supplement and he ended up giving me a small bottle of this:

https://www.fishersci.ca/shop/produ...rue&searchTerm=BP366500&searchType=RAPID#tab5

He's not into reefing, he's just a scientist friend that I ask my chemistry questions to, so he probably didn't look into it and just told me it's 99% KCl, but I noticed the spec sheet mentions 5 ppm MAX of Pb. Is that something I should be worried about? Or would this be an alright form of KCl to add.

Randy Holmes-Farley · Feb 11, 2017

That's a good product with a good specification.

Has your tank been running a long time? If by chance the test is off (I'm not certain that the standard he used is the best way to test such a kit), boosting potassium from 400 ppm to 500 ppm might be a significant problem. Potassium wouldn't usually get that low unless it has been depleting a long time.

3FeetReef · Feb 11, 2017

Thanks Randy.

The tank has been running a little over a year now, SPS-dominant and I started with zeovit about 3-4 months ago and saw some great results at first but then I lost a little polyp extension on a few acros and the colors started seeming more pale, so someone on the zeovit forums told me to test potassium and it came in less than 300 the first time I tried with a Salifert kit. Worth mentioning other parameters were where I expected them to be, and this was really the only thing that was massively off.

That's essentially when I got my friend to test it for me. He wasn't totally sure if it would read it properly since he just diluted the 1000 ppm Reference with RODI water to get to 400, and the kit measured 400 as well when he tested, so he figured it couldn't be that bad. He did everything using his lab pipettes and such, so it was probably a bit more accurate than me with the included syringe. He offered to run it through his lab's ICP this week as well if I really wanted, so I may give it to him to check either way.