ORP reading fluctuating with fluorescents on/off

[ssilcox]

Quick couple questions -

Just got a new 100 mg/hr Red Sea ozonizer. Started running it yesterday. I cleaned my probes well before starting the timer program with the ozone.

Anyway, I have not seen an increase in my ORP at all. I started it out at 50%, then today bumped it to 100%, but havent seen any changed in ORP other than the normal increase at night (~300), and decrease during the day (~250). How quickly should the ORP be affected by the ozonizer? Also - when my actinics turn off I get a 40 point jump in ORP. From 250 - 290. What could be causing that interference? FYI - I do not use the serial cable for aquanotes.

Also - am I supposed to using the pH compensation option? Haven't found a clear answer for that yet ...

 

[clp]

pH and ORP and inversely correlated. For every 1 unit change in pH the ORP will change by about 58 mV. Typically ORP will be highest in the morning (pH lowest), and lowest at night (pH highest). If you turn on pH compensation in the ORP setup section of the controller, then the AquaController will compensate for this correlation. Note that the industry norm is will pH compensation off, so if you turn on pH compensation your ORP readings are not comparable to other non-compensated ORP readings. It sounds like you have pH compensation turned on.
How quickly your ORP changes with ozone injection depends on the size of the tank, amount of ozone, and the bioload in the tank.
The lights must be emitting a bunch of RF interference. Please try the following:

- The reflectors on your lights are grounded.
- Physically separate the ballast cord(s) from the ORP probe and cords.

Curt

 

[ssilcox]

Curt -

Thanks for the tip on the reflectors. After grounding everything, the ORP reading came right to life. No wierd fluctuations with the fluorescents anymore, and it seems to be working well with the ozone now.

Thanks!