ORP is Practically Useless!

ca1ore · Dec 20, 2017

Setting up my new apex and I'm seriously considering not bothering with ORP as I find it a completely useless measurement. Been slavishly monitoring it for close to 30 years in my tanks. Since I stopped using ozone in about 1994, I have literally never done anything as a consequence of fluctuating levels. Just yesterday, for example, I get an alert from my old apex that ORP has dropped below 250. Actually it dropped to 205 from its normal level of about 330. Why - no clue! What happened - nothing that I could see! What did I do - waste 15 minutes looking around and then did nothing! By this morning, levels had returned to 330 or so, nothing amiss. Useless .....

ReeferCub · Dec 20, 2017

Just the other day I expressed similar sentiments about monitoring ORP using my apex! There is no practical use of monitoring ORP. At least I could not find any.
By the way, my ORP only drops significantly when I make a water change. And usually it just makes a reverse curve of pH value.

saltyhog · Dec 20, 2017

I agree.

csb123 · Dec 20, 2017

As is pH monitoring, unless you need it as a fail safe for your dosing.

Waters · Dec 21, 2017

Randy Holmes Farley has a huge article on the subject.....I monitor it but I agree, doesn't do anything for me.

Randy Holmes-Farley · Dec 21, 2017

csb123 said:
As is pH monitoring, unless you need it as a fail safe for your dosing.

I don't agree that pH monitoring is similarly useless, but I do agree that ORP is not particularly useful and, IMO, it is not even established that ORP impacts most organisms we keep, or if it does (perhaps through heavy metal speciation and hence bioavailability), which value ranges might be optimal.

ca1ore · Dec 21, 2017

I find monitoring (and in rare cases, controlling) pH to be very useful, particularly because I run a CaRx. In the Summer I have low pH issues from ambient CO2 levels in my house. Though running fresh air to my skimmer has proven singularly ineffective, a blower pushing outside air into the basement sump,room makes a sizable difference. pH levels trigger this fan.

csb123 · Dec 21, 2017

ca1ore said:
I find monitoring (and in rare cases, controlling) pH to be very useful, particularly because I run a CaRx. In the Summer I have low pH issues from ambient CO2 levels in my house. Though running fresh air to my skimmer has proven singularly ineffective, a blower pushing outside air into the basement sump,room makes a sizable difference. pH levels trigger this fan.

I would gently counter that a cheap pH test kit would be just as useful to do this (or a Ranco temp controller, arranged to monitor outside temps.)

ca1ore · Dec 21, 2017

csb123 said:
I would gently counter that a cheap pH test kit would be just as useful to do this (or a Ranco temp controller, arranged to monitor outside temps.)

..... and I would gently disagree.

Toky916 · Dec 21, 2017

If you have apex why would you use anything else to control your Ph or test with a test kit. People are not going to test every part of the day lol.

Chuk · Dec 21, 2017

I agree orp without ozone is essentially pointless. More like a nice to know if you already have it but definitely not required.

revhtree · Dec 21, 2017

I also do not bother with monitoring ORP numbers. Sometimes it's interesting to see it fluctuate with things you do to your tank.

BoomCorals · Dec 21, 2017

revhtree said:
I also do not bother with monitoring ORP numbers. Sometimes it's interesting to see it fluctuate with things you do to your tank.

Ditto!

Streetcred · Dec 21, 2017

I 'monitor' ORP trends over weekly periods to keep a check on water quality and any impending issues. This is not a deliberate activity as my controller measures and logs the ORP on an hourly interval and I just put it to some interesting use.

User · Dec 21, 2017

csb123 said:
I would gently counter that a cheap pH test kit would be just as useful to do this (or a Ranco temp controller, arranged to monitor outside temps.)

What’s the link between outside temperature, and the pH of the tank?

Just curious, kinda new to the complexities of reef chemistry.

Thanks

TommyPePe · Dec 22, 2017

Agree 100% on ORP
Must say, imho, the Apex Salinity monitor seems equally useless

JonasRoman · Dec 22, 2017

ca1ore said:
Setting up my new apex and I'm seriously considering not bothering with ORP as I find it a completely useless measurement. Been slavishly monitoring it for close to 30 years in my tanks. Since I stopped using ozone in about 1994, I have literally never done anything as a consequence of fluctuating levels. Just yesterday, for example, I get an alert from my old apex that ORP has dropped below 250. Actually it dropped to 205 from its normal level of about 330. Why - no clue! What happened - nothing that I could see! What did I do - waste 15 minutes looking around and then did nothing! By this morning, levels had returned to 330 or so, nothing amiss. Useless .....

I agree!

My apex at the moment measure orp and pH in calciumreactor. As I am going to convert to only Balling and I do not need my nitratereactor since long time any more , I have actually only one measuring function left at the moment for my Apex, pH in tank. All units today(at least mine) have almost always separate/ own computers and regulatory functions, like the light, wave pumps, ATO, feeding units. So in My case when taking away the calciumreactor and orp of same reason as you say, says Nothing, My apex at the moment is a little alone just measures pH and temp in tank.(Well, also get dKH values from Alkatronic).

The only use for orp I think is when measure and regulates a nitratereactor, there it works like the pH electrode controls the ca reactor.
But apex can not measure negative orp so I had to do a crossover bnc cable myself. In that case I really had use of orp. But measure in the tank. Agree 100%, put the money in something else, like for instance a nice refugium light?..etc

Jonas

ca1ore · Dec 22, 2017

neilp2006 said:
What’s the link between outside temperature, and the pH of the tank?

There isn't one.

JonasRoman · Dec 22, 2017

But I disagree that measure pH is useless. pH measure I would never take away. It fluctuates and tell me a lot of several things and also give me reason sometimes to do actions

Randy Holmes-Farley · Dec 22, 2017

ca1ore said:
There isn't one.

Except that people open windows more when temps are suitable and less so when it is too hot or too cold.

Also, we had a thread where someone noted a pH effect due purely to temps outside (cold fronts showed a rise in pH), and I posted a study that showed there was more natural leakage/convection through a home in terms of air turnover if the air temp outside was much lower than the air temp inside.

Cold, fresh air leaks in at lower levels, warms up and gathers CO2 along the water, and leaks back out again at higher levels.