Erratic PH Readings after UV Sterilizer Installed

[fdevans]

Hi R2R,
Yesterday I installed a new UV Sterilizer to combat some dinos. I noted the time I installed it so I could track results as 3:30pm (December 29th). Since that time I've noticed very erratic PH readings from my Apex PH Probe. Curious if anyone knows why this might be happening? I do have some calibration solution and plan on doing a cleaning and re-calibration in the next few days. Any other thoughts what could cause this? Below is a graph including the prior day and the time since installation. Notice the more frequent jumps up and down since 3:30 install.

 

[SteveMM62Reef]

Move the Sensors away from the UV and UV Transformer. Also some LED Lights, DC Drive Pumps, can Cause bad readings from pH Monitors.

 

[Garf]

Even power cords crossing over the probe wires can cause problems, worth checking.

 

[fdevans]

OK. That's a good tip. I might have moved things around too much in the equipment cabinet. I just untangled the PH probe a bit and moved the larger power items farther away. I'll check the graphs again in a few hours.