How to run ozone

[Calireefer92]

Hey reefers I just purchased Poseidon 200 Ozone Generator I have a 200 gallon tank. At what orp should I run it and how often, and how long?

 

[Randy Holmes-Farley Verified Community Expert]

Hey reefers I just purchased Poseidon 200 Ozone Generator I have a 200 gallon tank. At what orp should I run it and how often, and how long?

Ozone and the Reef Aquarium, Part 1: Chemistry and Biochemistry by Randy Holmes-Farley - Reefkeeping.com

Ozone and the Reef Aquarium, Part 2: Equipment and Safety by Randy Holmes-Farley - Reefkeeping.com

Ozone and the Reef Aquarium, Part 3: Changes in a Reef Aquarium upon Initiating Ozone by Randy Holmes-Farley - Reefkeeping.com

ORP is way more complicated than anything else we measure, and ORP is not really something to target (despite many folks recommending otherwise). When using ozone, ORP is mostly useful to be sure you are not adding too much ozone. While I'd recommend reading these linked articles before using it, here's the pertinent part related to your question:

So with all that background discussion behind us, here are my recommendations for ORP monitoring and ozone control in reef aquaria using a properly sized ozone generator that appears to be working, and a properly calibrated ORP meter:

1. If the ORP never seems to rise above 375 mV after initiating ozone, do not worry about controlling the ozone or the ORP. Just let it run full out. Also, do not worry about needing a larger generator, assuming it has driven up the ORP by at least 25 mV above where it was before adding ozone. It is likely accomplishing the necessary tasks (such as making the water clearer). Only if some other aspect of ozone use is unsatisfying (e.g., lack of water clarity) would I look for other options such as a larger ozone generator or a better contact chamber.

2. If the ORP starts above 375 mV, or rises there during ozone use, using an ORP controller would be valuable to prevent the ORP from rising too high. Use the controller to shut off the ozone when the ORP rises too high. Another option would be to shut off the air flow to save the dryer's media, but be sure that water cannot flow back into the ozone generator if the air stops. I would set the ORP target somewhat above the baseline ORP in the absence of ozone - at least 350 mV, maybe 400 mV, but never above 450 mV.

 

[CasperOe]

I run mine using the Neptune ORP probe up to 450. I run ozone through a seperate, smaller skimmer and twomhours every night.

Here's my code.

Fallback ON
Set ON
If ORP < 300 Then ON
If ORP > 450 Then OFF
If Time 01:00 to 23:00 Then OFF
If Output SKIMMER = OFF Then OFF
If Power Apex Off 000 Then OFF

 

[Pistondog]

If your goal is de colorizing the water, a few hours every 3 or 4 days should be enough.