In a simple words, what is the ORP?

[wesamazmy]

I tried to read a lot about the ORP, but I am confused!

Is there any simple definition for ORP? and should I measure it regular base such as PH, Alk..etc
What is the best level for the reef tank?

Finally how it dose will kill the most of bacteria in my tank in few seconds?

Thanks for all!

 

[marine2463]

Following

 

[Rockhead]

I have a opr meter on my tank and have been told not to worry about it to much unless you are using ozone, mine runs at 430-500 most of the time, I'm really not sure what makes it rise or lower, I have noticed that now that the Windows are open it seems to be higher then winter .

 

[twilliard]

Here is Randy's article
ORP is not the easiest thing to understand

http://www.reefkeeping.com/issues/2003-12/rhf/feature/

 

[NeptuneGarden]

ORP is measure of the reactivity of the available dissolved oxygen in the your water.

Oxygen likes to react with biological contaminants. A higher ORP reading means there is more reactive O2 atoms available in water. Low ORP usually means you have lots of contaminants (i.e. dirty water) that is reacting with O2. A high ORP means you have clean water. Too high of an ORP (usually from injection Ozone is only way this can happen) means there is too much O2 and it can start burning off good contaminants,i.e. bio-bacteria.

That's not really right, but pretty close in laymen terms.

Is a more in depth explanation from a pool sight
http://www.rhtubs.com/ORP.htm


ORP really only needs to be monitored if injecting Ozone, as others said. It's a good way to keep track of not injecting too much. It is also a good indicator of overall water column cleanliness and the it's potential to keep itself clean through the natural oxidation of contaminants. If lots of contaminants are being oxidized than you will have lower ORP readings, but is not necessarily an indication that something is "wrong"/

 

[wesamazmy]

I have a opr meter on my tank and have been told not to worry about it to much unless you are using ozone, mine runs at 430-500 most of the time, I'm really not sure what makes it rise or lower, I have noticed that now that the Windows are open it seems to be higher then winter .

Here is Randy's article
ORP is not the easiest thing to understand

http://www.reefkeeping.com/issues/2003-12/rhf/feature/

Actually I read all this article before I submit my thread! I totally ended as I didn't read anything I was seeking for advices as a beginners in this hoppy, shall we concerned by this! is it really risk? and what we can do to prevent? the topic is complicated, I understand the most topics before self learning, but this not sure!

 

[twilliard]

Hence seeing the drop in ORP from the use of h2o2

 

[Randy Holmes-Farley Verified Community Expert]

In general, ORP is not worth measuring unless you add adding oxidizers such as ozone, and thenonly to know you are not adding too much. On its own, ORP is not very useful.

FWIW, I don't think it is a useful measure of dissolved oxygen. It is really independent of O2 levels, but rather is a measure of the oxidizing power of the water, which, as noted is impacted by organics, but is really carried by redox active trace metals and the different forms they have.

 

[wesamazmy]

In general, ORP is not worth measuring unless you add adding oxidizers such as ozone, and thenonly to know you are not adding too much. On its own, ORP is not very useful.

FWIW, I don't think it is a useful measure of dissolved oxygen. It is really independent of O2 levels, but rather is a measure of the oxidizing power of the water, which, as noted is impacted by organics, but is really carried by redox active trace metals and the different forms they have.

Thank you for your answer, clear and direct to the point, really appreciated!

 

[wesamazmy]

ORP is measure of the reactivity of the available dissolved oxygen in the your water.

Oxygen likes to react with biological contaminants. A higher ORP reading means there is more reactive O2 atoms available in water. Low ORP usually means you have lots of contaminants (i.e. dirty water) that is reacting with O2. A high ORP means you have clean water. Too high of an ORP (usually from injection Ozone is only way this can happen) means there is too much O2 and it can start burning off good contaminants,i.e. bio-bacteria.

That's not really right, but pretty close in laymen terms.

Is a more in depth explanation from a pool sight
http://www.rhtubs.com/ORP.htm


ORP really only needs to be monitored if injecting Ozone, as others said. It's a good way to keep track of not injecting too much. It is also a good indicator of overall water column cleanliness and the it's potential to keep itself clean through the natural oxidation of contaminants. If lots of contaminants are being oxidized than you will have lower ORP readings, but is not necessarily an indication that something is "wrong"/

Thank you, also clear

 

[Randy Holmes-Farley Verified Community Expert]

Thank you, also clear

Clear, but unfortunately, not correct.

 

[NeptuneGarden]

Clear, but unfortunately, not correct.

Yeah, but it puts it in terms the average Joe can relate to. You start talking free electrons and redox potentials and people just get this blank look because they have no frame of reference of what on earth you are talking about. Heck, I get lost trying to wrap my head around it. I was never any good at chemistry.

I always tell people not to worry about it. I've never tracked or measured ORP, fresh or saltwater, and not a fan of ozone injection. (seen too many horror stories)

 

[fab]

I believe the "average Joe" prefers to know when he does not understand something over unwittingly accepting a falsehood. Personally, I am perfectly comfortable knowing that I only almost understand ORP and feel fortunate for knowing that important fact as I watch with rapt attention to ORP's mysterious meanderings across my plots and charts.

Average Joe
aka, fab

P.S., I am very grateful that we have qualified, knowlegeable subject matter experts in the forum to help us improve our knowledge, elevating our awareness as aquarists above alchemy, suburban folklore and false political correctness.

 

[NeptuneGarden]

P.S., I am very grateful that we have qualified, knowlegeable subject matter experts in the forum to help us improve our knowledge, elevating our awareness as aquarists above alchemy, suburban folklore and false political correctness.

I agree, but go back and read the original ops question. He was wanting someone to dumb it down and give him an answer that he could put into context he could grasp. Like explaining the color red to a blind person. You're never going to be right in your explanation, but you can at least give them a sense of it they can relate to.

Randy's artcl. are definitely a treasure trove.

 

[wesamazmy]

Thanks for all of you, definitely my understanding before I submited my question is not what I learned from your different answers, all what I want from the beginning to know when I could need to test ORP, I do believe that keeping the setup of the tank simple as much as possible can save a lot of effort in maintenance and testing.

 

[charlieborg]

What does Apex Fusion read ORP in? Mine is 2.83? So is this in mv?

 

[Randy Holmes-Farley Verified Community Expert]

What does Apex Fusion read ORP in? Mine is 2.83? So is this in mv?

you certain is is not 283 mv?

 

[JimWelsh]

A wee bit off topic for what the OP was asking, but some light reading on the subject can be found here: https://chem.libretexts.org/Bookshe...l_Chemistry)/Electrochemistry/Redox_Chemistry