POsitive & Negative ORP value

[sfchoong]

Hi Bro / Sis,

Need some expert view on why my PinPoint ORP meter have both the positive & negative readings. They switch over around 10 to 15 mins. The following are reading on varies meters in my tank.

PH - 7.3
Temp - 29.5 C
ORP - 345 & -086 (Day)

ORP - 325 & -125 (Night)

All my fishes & rays still eating well and WC as usual (twice a week 30%).

Thanks

 

[epond83]

As far as i know most people don't worry about ORP on a freashwater tank because freshwater hold oxygen better tehn saltwater. As for your question i have no idea since i've never used one. Have you read throught the instructions if they came with any, or look the instruction up.