AC3 ORP readings opinions

[DrBDC]

I think something is wrong but I'm ordering some calibration solutions to verify. I'm getting an ORP reading that tops at 408 today with a drop about 20 as the day goes on. I do do a lot of water changes and have macro growing well and a sump bigger than the main tank. But,,,,, I can't be that high. I'm not using the pH compensation or it would be in the 460's.

I'm NOT using ozone injection yet either.

I do have an ozone generation air purification unit in my sump room which produces 565 mg/hour but 1 of the 2 plates are removed giving about 280ish. This is in the whole room which has ventilation due to the furnace in there and when my 1 1/2 y/o is in bed or napping I have the door open too. The only way that ozone would be getting in is from my cc skimmer linear piston air pump drawing from the room and from surface agitation of the stock tank sump and of course where the overflows hit the waterline. I can't imagine much from that though. Maybe 10 mg/hour or could I just be underestimating how much is making it to the water from the atmosphere and air pump?

I've just hit the 2 week mark tomorrow so it should be just about settled in and I haven't seen much upward change in the last couple days maybe an increase of 5 in the peak. It started about mid 200's and I've gradually rose over the two week period. In two weeks I can't have a dirty probe yet or ??

 

[DrBDC]

I cleaned it in vinegar and it dropped to 270ish and this morning its at 308. Seems like it got dirty quick even though to the eye it was really clean still. So I guess that's on my weekly maintenance schedule to swish it around in vinegar.

 

[dhoch]

I had that as well till I callibrated mine.

Now it runs where I would expect (in the ~280-320 range) most of the time (minus water changes, and right after feeding).

Dave

 

[imbuggin]

calabrate the orp

calabrate the orp

can you explain how you calibrated the orp probe? The directions are not clear. They tell you to mix the ph calibration fluid with something else but never elaborate?? thanks for any help. I was getting crazy high readings as well cleaned it in vinigar and tried to calibrate it with the ph fluids.

 

[DrBDC]

I'm not sure all the places you can get it but here are a couple options I found:

http://www.sensorex.com/products/orp_electrodes/accessories/ORP_solutions.html

http://www.coleparmer.com/catalog/product_view.asp?sku=0547860

thereefstop.com also is able to get the solutions for an octopus or some other neptune competitor but doesn't have them listed on the site yet. He did a major site update/change but hasn't added new products this week. Anything he doesn't have listed you can tell him and he'll get the contact and list it usually w/in a day or so. But anyway, if you hit contact me he'll get back to you with it.

 

[dhoch]

imbuggin,

You need to get 2 sets of solutions, the problem is they are volatile (?) (i.e. they don't keep there concentrations long, so you have to mix them up right before you test them).

The sensorex.com solution is what I used (in DrBDC posts)... it involves 3 basic products: pH 7 solution, pH 4 solution and quinhydrone...

The kit cost ~$50 or $60, but you have calibration fluid to last you a long long long time... plus you get pH 7.0 and pH 4.0 calibrations as well.

You basically take the 3 beakers included, mix 7.0 and quinhydrone till saturation (it doesn't take a lot), mix 4.0 and quinhydrone (again it doesn't take a lot).

Then do your 2 point calibration via methodology in manual (rinse in the 3rd cup of distilled water between each calibration).

Dave

 

[bvoss]

I have to clean mine every few days to get a realistic reading. The reading climbs as film builds up on the probe. I clean it every 2 or 3 days with a Q-tip in vinegar.