Ozone not rising

[MarcinPl]

I am getting sick of fighting ORP.
I bought ozone generator which at the beggining worked well. Overtime, after a water change I couldn't rise my ORP
I went throught everything: Cleaned and checked the orp probe (I use Neptune's) accuracy - the probe seems to be working well.
So I changed the probe position - nothing, my orp wont go above 240
I changed the ozone generator. I actually went throught 3 different generators including oversized ones. Nothing
I changed the ozone connection hose and probe placement multiple times - nothing

Any ideas ? Maybe someone had similar issue ?
I also use UV and carbon

 

[Jay Hemdal Verified Community Expert]

I am getting sick of fighting ORP.
I bought ozone generator which at the beggining worked well. Overtime, after a water change I couldn't rise my ORP
I went throught everything: Cleaned and checked the orp probe (I use Neptune's) accuracy - the probe seems to be working well.
So I changed the probe position - nothing, my orp wont go above 240
I changed the ozone generator. I actually went throught 3 different generators including oversized ones. Nothing
I changed the ozone connection hose and probe placement multiple times - nothing

Any ideas ? Maybe someone had similar issue ?
I also use UV and carbon

How did you check the ORP probe? Those are often the weak point in applying ozone. Is the probe connected to a controller? If so, is the ozone generator running in conjunction with it? How often is it running?

Here is a basic article I wrote on ozone use:

https://www.reef2reef.com/threads/ozone-use-in-marine-aquariums.1089997/

 

[MarcinPl]

Hey Jay! I did read Your article even sometime ago. It's a good one and thanks for writing it.
So - I checked my ozone probe with calibration fluid (it was within 20 mV of the value).
I also cleaned the probe. The probe behaves correct - when put out of water, ORP quickly goes down, and comes back to original level when put back (although this takes some time).

Ozone generator is controlled by my Apex - it should switch it off whenever ORP exceedes 300. This doesnt happen because my ORP doesn't rise.. I have no idea why it used to raise nicely, and now it is as if I did not have the generator connected (although I tend to smell the ozone in my sump). Also at the begginings, some months ago, when I connected ozone after some break, I could smell it decomposing organics (now I don't)

I also tried running ozone with pauses - like 40 mins on, 20 mins off - but no results as well..
So.. dang - I am out of ideas
As I've mentioned - I changed the ozone generator and connection to skimmer multiple times (I use Royal Exclusive double cone, ozone is connected directly to the pump intake)

 

[Jay Hemdal Verified Community Expert]

Hey Jay! I did read Your article even sometime ago. It's a good one and thanks for writing it.
So - I checked my ozone probe with calibration fluid (it was within 20 mV of the value).
I also cleaned the probe. The probe behaves correct - when put out of water, ORP quickly goes down, and comes back to original level when put back (although this takes some time).

Ozone generator is controlled by my Apex - it should switch it off whenever ORP exceedes 300. This doesnt happen because my ORP doesn't rise.. I have no idea why it used to raise nicely, and now it is as if I did not have the generator connected (although I tend to smell the ozone in my sump). Also at the begginings, some months ago, when I connected ozone after some break, I could smell it decomposing organics (now I don't)

I also tried running ozone with pauses - like 40 mins on, 20 mins off - but no results as well..
So.. dang - I am out of ideas
As I've mentioned - I changed the ozone generator and connection to skimmer multiple times (I use Royal Exclusive double cone, ozone is connected directly to the pump intake)

Well, I guess you've tried tracing your ozone output? *Carefully* sniffing in the skimmer cup, then working backwards to the generator? You don't want to fry your nose, but a careful cupping of your hand and wafting it to your nose will tell you if there is ozone at that point in the system. Then, just work backwards through the system. I once found a clog in a commercial system, where nitric acid from the feed air being too damp had built up inside a fitting.

 

[jmaneyapanda]

Where is your ozone generator located? Are you running an air dryer? These could impact the quality of ozone produced.

BUT....... chasing an ORP number by using ozone is not a wise pathway. ORP probe, at best, are useful for monitoring trends in ORP, rather than absolute numbers. Im strongly of the advice of "trust your eyes". Do you see an issue in the aquarium you hope to have ozone resolve? If not, then (presumably) thinking your water is "dirty" because your ORP isnt 300 mv, and using ozone to try to chase that is foolhardy. This is all a elaborate presumption I made as to your rationale, so Im just spitballing.