Orp and nitrates

bevo5 · May 15, 2016

hi all. I've read all the orp articles that people usually link to whenever an orp question is posted. I just can't sort out one detail.

I recently set up cheato in my fuge and its growing like crazy. Bonkers fast. My orp used to be at about 400-420. Now it hovers right at 340.

I test for nitrates but I hate those kits. Always hard. I think they're about at 10 which I know is pushing the limits.

So question. The cheato is obviously eating nitrates since its growing so fast. Would the lower orp level be a result of the nitrate level coming down or just a coincidence? I'm not aiming do an orp number, I guess I just like thinking the cheato is working.

Thanks.

Randy Holmes-Farley · May 15, 2016

ORP is not impacted directly by nitrate. So changes in nitrate do not alter ORP.

The chaeto may be raising pH by consuming CO2, and that lowers ORP.

The chaeto may also be releasing organics to the water, which will tend to lower ORP.

bevo5 · May 16, 2016

Well - dang! I thought I was seeing some positive results of the chaeto - but hey, thanks for the info.

I know it's gotta be doing something positive as it is for sure growing pretty quick. Fills up my fuge weekly...