How Quickly Should I Raise ORP With Ozone?

splix · May 4, 2017

I've started dosing ozone into my 125g FOWLR. I set the ORP probe in 24 hours before I started to dose and it was hovering around 165. I've started dosing ozone around 3 hours ago and it's up to 188 as I'm writting this.

I'm pushing only 25 mg/hr per the manual which gives me around 5 mg/hr per 25 gallons. The manual states run 5-15 mg/hr per 25 gallons.

I've got my apex set to kill the ozone dosing at 250 currently. I dont want to raise it too much too fast. I figured 100 ORP for 2 weeks, then let it raise 50 ORP each week after that until I'm around 350.

Is this safe with how fast I'm raising ORP?

Cory · May 5, 2017

splix said:
I've started dosing ozone into my 125g FOWLR. I set the ORP probe in 24 hours before I started to dose and it was hovering around 165. I've started dosing ozone around 3 hours ago and it's up to 188 as I'm writting this.

I'm pushing only 25 mg/hr per the manual which gives me around 5 mg/hr per 25 gallons. The manual states run 5-15 mg/hr per 25 gallons.

I've got my apex set to kill the ozone dosing at 250 currently. I dont want to raise it too much too fast. I figured 100 ORP for 2 weeks, then let it raise 50 ORP each week after that until I'm around 350.

Is this safe with how fast I'm raising ORP?

Id be more inclined to set it to 15mgg/h than rely on a probe. Probes if not manufactured correctly or calibrated correctly can give false readings. Slow and steady

Randy Holmes-Farley · May 5, 2017

I personally do not think ORP should be the target or goal in using ozone,, except to not have it get too high.

I expect that if you boosted ORP by some reasonable amount (a few tens of mV) then it is going to do all the yellowness reduction it will, and that's, IMO, the only reason to run ozone.

These have more:

Ozone

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

jason2459 · May 5, 2017

Besides ORP the more ozone you push through I'd worry more about filtering it through GAC. (in the atmosphere and water)

splix · May 8, 2017

Tested the probe with that 400mv solution you can get for cheap. After around 20-30 min the probe read 402 orp and stayed there so I know the probe is ok. There really isnt much calibration you can do with an ORP probe and apex outside of the price of just buying a new probe.
I'm only using ORP as an ozone safe guard.
All ozone exits, air and water have GAC

I'm running my ozonitor at 15 mg/hr per 25 gallons per the manual, which is holding my ORP at just below 300.

Randy Holmes-Farley · May 8, 2017

splix said:
Tested the probe with that 400mv solution you can get for cheap. After around 20-30 min the probe read 402 orp and stayed there so I know the probe is ok. There really isnt much calibration you can do with an ORP probe and apex outside of the price of just buying a new probe.
I'm only using ORP as an ozone safe guard.
All ozone exits, air and water have GAC

I'm running my ozonitor at 15 mg/hr per 25 gallons per the manual, which is holding my ORP at just below 300.

That all sounds good to me.

splix · May 8, 2017

My LFS (whom I trust a lot), as well as reading a lot of other ozone articles are saying to push ORP to the 375 range. In order for me to do that though I'll have to go beyond the 15 mg/hr per 25g of ozone. I'm not sure which rule to break haha. Let ORP stay low or push ozone beyond 15.

Edit: I completely did not notice it was THE Randy Holmes-Farley replying to my thread.
Randy I've gone through your articles as well. Thats why I'm leaning towards letting ORP do what it does and sit where it is and keep ozone dosing at 15 mg/hr per 25g.