More, different PH issues!

[budsreef]

The PH probe I bought came out of the box with the tip dry so I rinsed it in ro/di and left it in the tank overnight. This morning it seemed to calibrate so I think it is ok. After calibrating it says my 120G is at PH 7.63. I took my probe that is connected to a Pinpoint PH monitor from the 24G, recalibrated it and tested the 120G. It says the PH is 7.83 so I'm not sure which to believe but the difference is slight enough I don't think it really matters.

While I had the probe out I went around to the other tanks to check the PH and all looked well until I tested the 70G in the basement, which had a reading of PH 6.5. A moment of panic set in, but I figured something had to be wrong with my reading since all the corals are doing just fine. I went back upstairs and tested each of the other tanks and they all still read normal so back to the basement to check the 70G again and it still read PH 6.5. I then checked the 20L which is attached to the 70G and it read PH 8.0. Back to the 70G and it reads PH 6.5 but it is the same water as the 20L. I went to the other side of the 70G and it read PH 8.0.

It appears the T5 lights or the ballasts were impacting the readings. With the Pinpoint monitor held close to the lights and ballasts it read anywhere from PH 5.0 to 6.5 but when I stretched out the cable so the monitor was away form the lights and ballasts it read PH 8.0. Has anyone else noticed this or is this a known issue with the monitors?

 

[bobz]

Wow. That sounds whacked! I'll check mine and see if I have similar results.
Bob

 

[wbholwell]

My ballasts screwed with mine too. I had to put the probe in my sump.

 

[budsreef]

I just checked it after the daylight bulbs turned off and it is ok with just one ballast with two actinic bulbs on. I have two ballasts running 4 daylight bulbs and will try to separate them tomorrow.

 

[fishfiend]

Are you running a CA reactor? Those have a return with lower PH.

 

[chauwall]

I have a Pinpoint pH monitor too and after several months of attempting to use it, the probe just kept going nuts-after quite a few calibrations. I don't use it anymore.

 

[budsreef]

Fishfiend;158794 wrote: Are you running a CA reactor? Those have a return with lower PH.

No CA reactor. It has something to do with the lights or balasts interfering.

 

[budsreef]

chauwall;158797 wrote: I have a Pinpoint pH monitor too and after several months of attempting to use it, the probe just kept going nuts-after quite a few calibrations. I don't use it anymore.

If T5s can cause the kind of problem I had, could that be an issue for you as well? They do work well under normal circumstances.

 

[sammy33]

Try taking samples from each tank to a neutral location with no interference (like the kitchen table). Read the samples and then read a calibration solution. Compare these to the readings you were getting "under the lights". Then try measuring at the tank under the lights again. This should allow you to verify if the tank electrics are interfering.

My ballasts goof up my digital thermometers if I get them too close. :huh: