Ozone - Potassium

cvicente · Dec 7, 2015

Hello Randy ! Can ozone deplete potassium ?

Randy Holmes-Farley · Dec 7, 2015

Ozone will have no impact on potassium ions.

cvicente · Dec 7, 2015

Thanks Randy, I asked because the K in my tank is very stable in the 400-420 range. I recently added an ozone generator and I've applying very small doses (25mg) in my 150 gal system. In 2 weeks my K plunged to 340 ppm and the only thing new in my system was the O3 generator.

jason2459 · Dec 7, 2015

Have you noticed more clarity in the tank and as a result more growth?

Randy Holmes-Farley · Dec 7, 2015

cvicente said:
Thanks Randy, I asked because the K in my tank is very stable in the 400-420 range. I recently added an ozone generator and I've applying very small doses (25mg) in my 150 gal system. In 2 weeks my K plunged to 340 ppm and the only thing new in my system was the O3 generator.

I'd double check it. I suspect testing error as that's a huge drop for any tank for almost anything you could change.

cvicente · Dec 7, 2015

Randy, I triple checked it with a Salifert kit, the reagents are almost new. Jason2459, the water is crystal clear. On the growth side, is too soon to determine, but there is huge difference on polyp extension. The small patch of cyano that I had is gone.

Randy Holmes-Farley · Dec 7, 2015

Try the kit on some new salt water.

Potassium itself cannot possibly react with ozone in any way.

As Jason suggests, growth might have picked up a bit if the water is clearer and more light is penetrating. Also, bacterial growth might give a little spurt due to suddenly bioavailable organics that were not digestible before the ozone.

But I can't see how either could suck down that much potassium in 2 weeks.

cvicente · Dec 7, 2015

Thanks Randy, I will try testing new salt water.

Randy Holmes-Farley · Dec 7, 2015

You're welcome.

Let us know what you find.

Randy Holmes-Farley · Dec 7, 2015

For anyone interested, I discuss the various reactions that ozone does do here, especially the first one:

Ozone and the Reef Aquarium, Part 1: Chemistry and Biochemistry by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2006-03/rhf/index.php

Ozone and the Reef Aquarium, Part 2: Equipment and Safety by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2006-04/rhf/index.php

Ozone and the Reef Aquarium, Part 3: Changes in a Reef Aquarium upon Initiating Ozone by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2006-05/rhf/index.php

cvicente · Dec 10, 2015

Hello Randy, this is what I have found so far. The reagents are good, I tested a fresh batch of saltwater and got a 390ppm result, very close to what the manufacturer states on the label. When I found the drop in K (last Friday) I adjusted the level during the weekend and raised it to 430ppm. This morning the level was 400 ppm, a 30 ppm drop in 4 days.

Randy Holmes-Farley · Dec 10, 2015

cvicente said:
Hello Randy, this is what I have found so far. The reagents are good, I tested a fresh batch of saltwater and got a 390ppm result, very close to what the manufacturer states on the label. When I found the drop in K (last Friday) I adjusted the level during the weekend and raised it to 430ppm. This morning the level was 400 ppm, a 30 ppm drop in 4 days.

A drop of 30 ppm in 4 days seems fairly unlikely to me. I don't know aboot the test you are using, but some K tests seem rather prone to variability.

I wouldn't dose more unless you get a continuing downward trend.

cvicente · Dec 10, 2015

It seems that Salifert potassium kit is out of stock everywhere ! I placed an order for a KZ potassium kit to see if I get similar results. I'll keep you posted.