High Redux

[riddler772]

I have a 150 Reef tank that been in very good shape for several years.About 3 weeks ago I added an Ozotech Poseiden ozonizer and MTC ozone reactor system with Milwaukee Orp controller.I set the Redux at 370 and for about a week and had positive results.In the evening I noticed the Redux would tend to overshoot the limits and go to maybe 420 so I lowered the set point to 350.Last Thursday at night the Redux went to 440.I assumed the controller was not reading correctly.On Saturday morning the reading was 530 and several fish were dead and the rest were breathing heavily.Fortunately I had been mixing 30 gallons of make up salt water.This lowered the redux and the other fish recovered immediately.Since last Saturday the Ozonizer and Reactor have been off.The redux has stayed at 530 ever since.I tested the probe with calibrating solution and it was very accurate.I called Ozotech and they adviced less oxygen so I tried turning off my closed loop circulation and protein skimmer for 4 and 8 hour periods with limited success.
The only effective treatment has been the addition of API marine stress coat on Wednesday that immediately lowered Redux to 200 and added Aloe Verra to replace damaged mucus on fish.After large initial dose at recommended strength 10 ml per 10 gallons after 18 hours the redux was back to 530.I have been adding smaller doses periodically to reduce the redux and heal the fish coat.
This is actually a condensed version of events.The 2 questions I have are how to safely lower High Redux and is daily use of Marine Stress Coat OK?
Thanks
Jeff

 

[Randy Holmes-Farley]

The measured redox is not of concern to fish. What is of concern is the toxic oxidizers that were added to the water. That said, I'd stop using ozone until you figure out a better way to control it.

These have more:

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

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

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

 

[riddler772]

The ozone was turned off last friday,almost a week agzotech has recommended turning the ozonizer back on at a lower setting to oxidise the chemical or organic agent that is causing the elevated readings.I just turned the ozonizer back on 1/2 hour ago and am monitoring it carefully.
The Stress coat causes an immediate drop in Redux but it comes back.
I know this is very strange.

 

[Randy Holmes-Farley]

No, do not follow their advice. Maybe there was a communication problem, but it is just plain stupid to add more ozone to try to get rid of an oxidizing agent that is elevating the ORP in an aquarium.

I think it is likely the ORP is not still that high, but adding GAC will help break down any still present oxidizers. Did you pass the reactor effluent over GAC before letting it get to the tank?

You might stick that probe into some new salt water and see what you get. That will tell you if there is a measurement problem (despite the calibration) and will also show if a water change will help.

 

[riddler772]

The return from the Ozone reactor goes thru a MTC carbon reactor with 1/2 pound of new carbon.I tried turning on the ozone for an hour but the Redux started climbing so I turnded off the ozonizer.I soaked the electrode cleaner for an hour then tested in Pinpoint 400 Orp/Redux Calibration solution.
I read the articles on Ozone at least 3 times which is why I decided on the MTC Ozone reactor system.
Like you my initial reaction is the probe is misreading.The testing
of the equipment and the fish reactions make me believe high redux.I was a Marine Engineer on merchant ships for 14 years and my primary responsibility was testing of boiler water and calbrating water testing equipment.Also 40 years+ of Marine Fish keeping.
I am baffled!

 

[Randy Holmes-Farley]

If you check the ORP in a cup of water outside of the tank, does it still read high?

Running the reactor without any ozone will serve to drive the water over carbon which my reduce the toxic oxidants.

 

[snorvich]

Yes, it sounds as if you need to recalibrate.

 

[riddler772]

I just bought a new unit. So both units will be on a foot apart in the sump.In 12 hours or so some resolution to the problem
Thanks
Jeff

 

[2dawghouse]

I might have missed it. But I noticed all your equipment was in place besides a carbon reactor. You are running carbon arent you?

 

[riddler772]

I am running a large cabon reactor built by MTC with at least 1/2 pound of new carbon.After 18 hours the new Milwaukee Orp is reading 533 redux the same as the original unit.Yesterday I started treating the fish with Kordans fish protector with good results.Most of the corals are doing well with a few exceptions.Last sunday I did my normal 30 gallon water change.Today I will repeat.
Still baffled!

 

[2dawghouse]

Are you running your ozone reactor effluent to fast through the carbon reactor? I honestly have no idea why your ozone would still be climbing to the 530's.

 

[riddler772]

Here are the facts.Ozone has been off for 8 days.The unit has been unplugged.8 days ago a 30 gallon water change and one today.I fully understand and agree the Redux should not be this high however there are 3 reasons why I believe the readings are correct.
1.In the past week on every other day the probe has been cleaned in electrode cleaner and tested with calibrating fluid.
2.Yesterday a new Orp meter was purchased and placed a foot away from the old unit in the sump with virtually the same reading.
3.Last Saturday,8 days ago,when the Redux climbed over 500 several fish died.All of the other fish were breathing heavily.When stress coat was added they almost immediately recovered.This is consistent with High Redux ie the fish mucus coat has been adversely hurt by being oxidized.Whenever subsequent addition of slime coat have been added during the week they respond positively.
My carbon reactor is both large and effective.I have been using it and my ATI 250 protein skimmer intermitently.
I am open to any possible explanations.

 

[Randy Holmes-Farley]

I'd do a water change in case there are high levels of oxidizers in the water.

 

[riddler772]

I did a 30 gallon water change today and a 30 gallon water change 8days ago.

 

[2dawghouse]

What about adding vodka? It would lower the dissolved oxygen in the water naturally and consume any nitrates and/or phosphates.

What is the pH of your tank right now?

 

[Randy Holmes-Farley]

Most folks do not report a big drop in ORP with organic carbon dosing.