Hydrogen sulfide ORP

[LobsterOfJustice]

Would hydrogen sulfide introduction affect ORP? I accidentally shut off flow through my sulfur denitrator for about 15 hours (recirc pump still running). This morning I flushed 4 gallons through the reactor until water was clear and no longer smelled. I also moved the outlet of the reactor to the skimmer inlet. I can monitor the ORP throughout the day from the apex, would that let me know if my measures weren’t sufficient and hydrogen sulfide was being introduced?

 

[Randy Holmes-Farley Verified Community Expert]

Yes, hydrogen sulfide is strongly reducing and will lower ORP substantially if it is getting into the water column.