Climbing ORP and high PH (Looking for help)

[Lou Raffael]

Hi everyone,
I have always had high PH and high ORP since getting my tank started three months ago. I've got a pair of clowns and three fire fish in the tank with some inverts and it doesn't seem to bother them but I'm a little nervous to start with coral with these readings. According to my apex my ORP is currently at 501 which is the highest it's read so far but it's been hovering around this number for a few days now. It's always consistently been over 400, usually close to 450 but recently it has climbed. My PH is also high always around 9.0 sometimes it dips below but also goes above to about 9.1 I tested the RO water and that was around 7.6 so I have no idea where it's coming from. It's a 90 gallon tank so I did a decent size water change the other day (35 gallons) hoping that would drop both readings but it only dropped them for a short time. They climbed back fairly quickly. Should I be worried about these readings, if so how do I lower them?

Thanks for your help!

 

[Mal11224]

It's really hard to say without knowing any other parameters. On my apex, as my ph rises, my orp falls and vice versa. My orp goes from 322 - 326 give or take. 501 is considered high. Have you checked your salinity, nitrates, ammonia and nitrites? Do you use ozone? Hi orp means that there is a considerable amount of oxygen in your water, which will also increase your ph.

 

[Mal11224]

Also, if your parameters are in order and your tank has cycled properly, you may want to check your probe. If your tank inhabitants are doing well, then it may not be an issue.

 

[Randy Holmes-Farley]

ORP NEVER gets too high on its own, and generally isn't a useful number unless you are using it to prevent ozone from being dosed excessively.

I am also 100% certain your pH is not 9, unless your water is milky white with precipitate. You need to recalibrate the pH meter with new pH 7 and 10 (or something similar). pH never gets too high unless you are using new artificial rock that wasn't adequately cured, or are overdosing limewater (kalkwasser).

 

[Lou Raffael]

Thanks Mal11224 and Randy, My salinity is 34.5-35.5 ish. Doesn't swing too much but stays in that range. Ammonia is 0, Nitrites are 0 and last time I checked Nitrates which was about a month ago they were between 2-5 (Closer to 5) using a Red Sea test kit and I do not use ozone.

I think you're both right and I need to re-calibrate my probes. I did it when I first started the tank but this PH thing is making me think they're not right.

My water is pretty clear, I used dead dry rock which sat in RO water for two months (Changed out several times) and then fully cycled in the tank before fish spiking it with ammonia, then down to watching it go down to 0, same with Nitrites then repeated.

I know my temp is a little high but that's because of a recent heat wave which really warmed the house. I see you are both in the northeast so you enjoyed the warm weather as well.

 

[Mal11224]

Yeah, I would definitely recalibrate the ph probe or use another test method. Also, don't trust the apex salinity measurement. It can be off sometimes. Should use a refractometer for accuracy. Might need to look into a chiller or cooling fan to blow into your sump. Certain corals do not do well with high water temps. May be something to consider if you see large changes in temp. Once you recibrate, you should be good to go. Wouldn't worry too much about the orp as long as your tank is healthy.

 

[Brandonsegula]

I never heard of any such thing as to high of an orp. Orp just goes where the tank is happy. Although your PH is high. I would do a water change and see if that helps. I always stress water changes. When something isn't right it best to figure out what is the reason behind the problem but a water change is always good to do regardless.

 

[Randy Holmes-Farley]

I never heard of any such thing as to high of an orp. Orp just goes where the tank is happy. Although your PH is high. I would do a water change and see if that helps. I always stress water changes. When something isn't right it best to figure out what is the reason behind the problem but a water change is always good to do regardless.

IMO, true pH issues (which this is not) are never best solved by a water change.