ORP change after water change.

[vio]

Just curios , why ? ORP change from 375 to 330 when i use Tropic Marine Pro.
Then if i use ESV , NO change same # ?!

Thank You.

 

[Gareth elliott]

Have you checked the orp of the newly made sw? Likely its lower than the aquarium dropping the aquariums orp after the pwc. Not sure if it would be anything to worry about since this is probably common during pwc and most of us dont have orp probes to even see that it is occurring.

 

[vio]

Have you checked the orp of the newly made sw? Likely its lower than the aquarium dropping the aquariums orp after the pwc. Not sure if it would be anything to worry about since this is probably common during pwc and most of us dont have orp probes to even see that it is occurring.

My probe still in sump , when i change 50 Gal. T.M. Pro ORP go down after few day come back to same # when i change same amount , 50 Gal, ESV ORP , NO change. May be nothing important , just weird.