ORP peaking after UV install

[Clueless_Reefer]

Call it not enough research or what have you...but I wasn't prepared to be dealing with my ORP going outside of the Apex's recommended range. Please reference the attached two photos. Basically ORP started peaking out of 450 tonight vs the second photo which is a typical week. I just started running UV on and off for a few days now but have been phasing it in more and more.

I noticed the leathers were sliming out a bit today and my my bubble wasn't as fluffy as normal - all other corals seemed fine. The only thing I can think of is both yesterday and today in the AM I dosed some Phosphate-E at below half dosage (been bringing down from .12). I basically waited 8hours before turning UV back on after dosing. All other readings are dead on for target reef aquarium honestly.

I turned it off for the night just out of being freaked out from never hitting 450+ before and in case the UV was doing this...

 

[blaxsun]

I don't think it's entirely related to the UV. Just turn the alarm off or increase the alarm threshold.

 

[Randy Holmes-Farley]

I do not believe that there is any concern that a normal aquarium UV is going to push ORP too high.

 

[Clueless_Reefer]

After turning off the UV last night I did get a noticeable drop - see the first arrow below. It did rise again throughout the night with a few dips. The second arrow is when I swapped out the filter socks this morning.

 

[Clueless_Reefer]

Appreciate the feedback - I spoke to Pentair Aquatics yesterday and they confirmed that having an air bubble up at the top out of the area where the bulb isn't a concern. I did see someone was posting previously that if air bubbles form inside the UV sterilizer that they can turn into Ozone and start raising the ORP. Any thoughts?

 

[takitaj]

I don't know about the ozone question but my ORP does the same thing when the UV has been running for a while. The bubble won't bother the unit at all. From the top of the outlet & up is air and I've had no issues for almost a year now.

 

[Clueless_Reefer]

@takitaj what do you see your typical ORP levels averaging at?

 

[takitaj]

Until I started using biopellets it would run in the 400's with UV and would drop with the UV off to 300's. Since adding biopellets it runs in the mid 200's.

EDIT: ORP depends on too many things to really tell you anything of much use. Sudden extreme changes might tell you something is amiss. Just feeding the tank can drop it 50 points. I watch the trends but have no idea what any of it means. It's more of a curiosity.

 

[Clueless_Reefer]

Latest update - apparently though unless you dose Ozone you really don't need to watch ORP?

 

[piranhaman00]

ORP is such a useless measurement, don’t worry or care about this.

 

[Randy Holmes-Farley]

Appreciate the feedback - I spoke to Pentair Aquatics yesterday and they confirmed that having an air bubble up at the top out of the area where the bulb isn't a concern. I did see someone was posting previously that if air bubbles form inside the UV sterilizer that they can turn into Ozone and start raising the ORP. Any thoughts?

You do not need ozone to raise ORP, and the usual wavelength of 254 nm for a UV breaks down ozone rather than making it. You need shorter wavelengths to make O3 from O2:

Ozone equipment manufacturer and ozone system integrators Ozone Production from UV Lamp Ozone Integration Experts

How is ozone produced from UV lamps answered here. We explain how UV wavelengths both destroy and create ozone and how it can be done commercially

www.oxidationtech.com

from it:

-UV light wavelengths shorter than 240 nm will create ozone via photolysis of the oxygen molecule.

-UV light wavelengths between 240-280 nm will destroy ozone via photolysis of the ozone molecule.