ORP is Higher Really Better?

[birdman]

For those that don't understand ORP or reduction potential here is a good article to read.
http://www.rhtubs.com/ORP.htm

Now we know the higher the reading, the more pure the water. We can use meters to monitor ORP or controllers to control additives such as Ozone to increase the OPR or purity of the water. But is this really best?

Maybe for humans, who like gin clear water. But what about the Koi. The biggest, best Koi grow the fastest in natural mud ponds, not gin clear water with high ORP readings. So, are we going about this wrong?

From smaller Koi, around 8 inches, we have gotten more growth this year out of our plant pond than out Koi pond. The Koi pond has clear pristine water and fed only the best. The plant pond has cloudy, murky water, and fed just Rangen Staple. I don't have an ORP meter to compare the two, but know water quality as we call it for our human wants is much better in the Koi pond than the plant pond.

SO? open for discussion.

[tnoble]

I don't have an ORP meter to compare the two, but know water quality as we call it for our human wants is much better in the Koi pond than the plant pond.

SO? open for discussion.

Steve, I think you may be surprised at the power of plants and the micro flora & fauna that lives in a planted pond. I have noticed the same phenomenon, getting better growth from a murky puddle, and ORP can actually be higher in the murky water, not often but I've seen it.

Travis

[anthonym]

I think there is confusion in why high orp numbers are desired by those who use items such as ozone. One reason is to have clear water . I do not think this is a matter of if hi or low orp is better for the fish . This is for the owner, to be able to view the koi in crystal clear water. This would be no different then having an aquarium and letting the water be green and cloudy verse clear. It is there for the viewing pleasure.
Also there is a huge benefit to health in keeping bad bacterial levels low.

The fact that "The biggest, best Koi grow the fastest in natural mud ponds, not gin clear water with high ORP readings" may not be correct. Maybe it is because these fish are in hundreds of thousands of gallons of water verse 5000-20,000 gallons and the water is constantly being flowed through which in and of itself would give a great orp reading.
You can have a high orp reading and have muddy water from clay. Just throw koi clay in your pond and watch the orp reading, there is little to no change. The clay is not lowering the orp but the water is very cloudy.

[Michael Cox]

Sorry for hijackn your thread Steve but the Oct/Nov issue that is at the printers now has an article on this very subject written by Michael Anderson.

Talk with you soon.

[birdman]

Sorry for hijackn your thread Steve but the Oct/Nov issue that is at the printers now has an article on this very subject written by Michael Anderson.

Talk with you soon.

Not Hijackn Michael, good to know it's coming.
Hey you bum, what are you doing on the computer? you should be out enjoying the convention.

[birdman]

So what numbers are we shooting for? What is good? What is bad?

[anthonym]

The numbers I watch are just the orp in my O3 reactor (in the 800s)to be sure its at peak performance and the orp from this o3 water going back to the pond which I keep under 400. All this said my pond water orp stays in the 250-280 range with a PH of 8.3 to 8.5 when all this is working properly.

[dick benbow]

I struggled to find an example to use, so we could come up with an understanding of ORP......for those trying to come to terms. Hopefully this will help.......

....many are aware of a test strip that you dunk in your pond water and it takes a small amount of time to get a picture of 5 or 6 individual readings. If something was out of line, we could get the specific
test kit for that item and do a more detailed investigation with a higher degree of accuracy.

Orp is similar in so much as it gives an overview that many individual concerns
are well. As we all know, the fact that water is clear in itself does not mean it is good wholesome water for our Koi to live in.

Mr Anderson's article will be something timely...thanks michael for recruiting and publishing

[stephen]

The numbers I watch are just the orp in my O3 reactor (in the 800s)to be sure its at peak performance and the orp from this o3 water going back to the pond which I keep under 400. All this said my pond water orp stays in the 250-280 range with a PH of 8.3 to 8.5 when all this is working properly.

You have learned Extremely well grasshopper. I do it a little different than you but obtain the same results If not manipulated, my pH is a mirror of yours. I don't pay any attention to the ORP in my reactor (7000 gallon lower pond with no fish). I monitor/control my water at the head of the streams about 40-50 ft before it enters the main pond body. I keep the water there at 250mv. The massive 1500-2000 gallons a minute water flow keeps the ORP at it's highest natural level.

Obviously, when I lower and maintain a stable pH via Reverse Osmosis like I am currently doing, the ORP is raised to it's natural level. Ozone is currently not kicked on.

Picture just snapped:

pH 7.34
Water Temp 85.4
ORP 385
Alkalinity 39 ppm
Hardness 38 ppm

It should be understood that the ORP is not due to the ozone but instead to the pH value. As Anthony and other real players have discovered, the ORP is gonna be what it is in the pond and that is determined by pH.

Anthony's water at ORP 250-280 mV is everybit as good as mine at ORP 385 mV with my pH at 7.34.

Cliffnotes Version: ORP is a pretty worthless measurement and doesn't really mean anything by itself. However; It can be a useful tool when adding any oxidizers to the pond tho.

Disclaimer: With all due respect to Michael Cox and his Absolutely Fabulous Magazine Koi Nations , Michael Anderson only has a minuscule understanding of ORP and doesn't understand it's relationship with pH and other variables. IMHO I would not place too much credence in that particular upcoming article of his. I am sure Michael is a wonderful person and great koi keeper, but when it comes to ORP he is a bit lost as is Jr.

[farne230]

Regarding the subject of Ozone; Stephen and Anthony, I have been looking at the Clearwater ozone generators they offer and have a few questions I thought I would ask you before Clearwater.

1. There are various corona units, besides the amount of ozone they can generate, what are the differences and uses, for example- pressurized units like you have Stephen verses they unit they suggested for me M15/cd?

2. How do you calculate what size ozone generator I require?

3. How do you calculate what size mixing vessel I would need?

4. Control methods, to assure safe operation?

Thanks,
Bob

[birdman]

So we know people with ozone are running ORP readings in the 200s or even 300s. But for those of us with out ozone where should our ORP readings be?
AND
Does higher ORP reading really make better/healthier water for the fish?
AND, with out adding ozone, what can the average person do to raise their ORP?

[gcuss]

So we know people with ozone are running ORP readings in the 200s or even 300s. But for those of us with out ozone where should our ORP readings be?
AND
Does higher ORP reading really make better/healthier water for the fish?
AND, with out adding ozone, what can the average person do to raise their ORP?

Hi Steve,

I'm no expert by any stretch, but as an example for you. With a freshly cleaned and calibrated ORP meter, I'm achieving 320-340 throughout the week at a PH of 8.1 - 8.4.

As far as healthy? I don't use mine to determine if my water is healthy, but I can follow trends in my water column by looking at the recorded numbers over time.

I don't have ozone but do change out 6% of my water daily. I believe I achieve my numbers by an extremely low stocking rate, a plant free pond, and lots of air.

Incidentally, I found my ORP to remain high during an algae bloom so clarity doesn't necessarily mean the ORP is up. Nor does murky mean its down...

Anyway, like I said, no expert here. But if that's any use to you...

Grant

[stephen]

So we know people with ozone are running ORP readings in the 200s or even 300s. But for those of us with out ozone where should our ORP readings be?
AND
Does higher ORP reading really make better/healthier water for the fish?
AND, with out adding ozone, what can the average person do to raise their ORP?

Good question Steve. The ORP should be close to the same with or without ozone. I did an interesting experiment a couple of years ago. I turned my pumps off and cranked the ozone full blast on my lower pond and maintained the ORP above 900 mV for several hours. This water was completely sterile. All organics and everything else was oxidized. I then turned the ozone off to observe how low the ORP would drop.

The pond pH was about 8.6 at the time of the experiment and the water temp was about 90. Results:

ORP before ozone was turned on was about 240 mV
ORP while ozone was on was above 900 mV
ORP about 30 minutes after ozone was shut off was about 250mV

The point here is that that water was completely sterilized and was devoid of any organics but the ORP dropped to about 250mV anyway. There was nothing I could have done to make that water any cleaner.

Next I took a 5 gallon bucket of that water with ORP and pH probes constantly in it. I slowly added tiny quantities of muratic acid. As the acid lowered the pH values, the ORP readings increased. I recorded about 10 different pH values along with their corresponding ORP values.

What I am trying to say Steve is that pH is by far the most important factor in determining your waters ORP value.

Does higher ORP make better/healthier water for the fish You want your ORP as high as it can be relative to the pH in your pond. Like I said earlier, Anthonys ORP 250mV water is equal quality to my ORP 385mV water assuming that ammonia and all other factors are are equal in both ponds.

How can you raise your ORP to it's max By doing the same things that you are probably already doing. Don't overstock, don't over feed, have sufficient filtration and maintain it, sufficient water changes and keep your dissolved oxygen levels as close to 100% saturated as possible. You could also inject carbon dioxide, acid or use R/O to lower the pH which in turn will raise the ORP.

Like I said earlier, ORP in itself is a pretty meaningless # that one should not chase. If you do the things mentioned above, you don't need to worry about ORP.

[anthonym]

Good question Steve. The ORP should be close to the same with or without ozone.

I had the same results through the winter months when my ozone is turned off. My pond gets covered in winter with water temps in the mid 55s,no feeding nothing dirtying the water . The orp never dropped all winter with no ozone running.

[six6guy]

I monitor my ORP because my pond is nestled under mature White Ash trees that drop tons or seed and leaf matter. It's a constant battle to clean skimmers, pump baskets, and pre-filter brushes. Anyway, the ORP reading gives me a positive indication about my water quality.

pH is 8.30 to 8.45 (dawn to dusk)
temp is 72F (dawn)
kH is BS'd up to 107ppm
gH is 143ppm
ORP is 300 to 325 but I watch for dips and swings.

I don't have RO nor an O3 generator, but I do carbon filter my city water. I typically change 20% per week broken down as two 10% changes. I'm starting to think about opening the valve and allowing my carbon filtered water to trickle, but my water bill is already outrageous.

Brad

[birdman]

Thanks for all the input everyone. Hopefully we all can learn something from this.