Coductivity-based ATO? Please share your experience.

cb684 · 06/02/2014, 01:18 PM

Hello all,
I am trying to get a sense for how reliable is to regulate my ATO based on the conductivity probe reading.
Any thoughts? Please share...

Mark Bianco · 06/02/2014, 04:39 PM

Are you referring to the salinity probe?

aquamanic · 06/02/2014, 05:01 PM

I don't think it would be a reliable method at all. I don't know how big your system is but it takes a lot of RO water to move the needle. If you had a system with 100g in it at a PPT of 35 and lost 5 gallons, the PPT would only move to 36.8.

These conductivity probes only have an accuracy of +/- 1 PPT. So your 35 PPT system could read 34 or 36 and be within the accuracy of the probe. Now you've lost 5 gallons of water and your PPT only moved .8 PPT outside the accuracy of the probe.

And that's a lot of water to replace at one time. Most people like to put in ounces at a time to avoid fluctuations.

I wouldn't do it. I'd use floats instead. Way more precise IMO.

wwanthony · 06/03/2014, 03:50 PM

In addition there is also a Temp element to the Cond readings.

I would not do it.

Reefvet · 06/03/2014, 04:23 PM

The idea comes up every few weeks after someone has seen this video.

kenargo · 06/03/2014, 06:15 PM

Don't do it!

Yes, a conductivity probe is a good tool for monitoring but not nearly accurate enough to use as a method to replace water and control salinity mix in a live environment.

06/02/2014, 01:18 PM	#1
cb684 Registered Member Join Date: Feb 2014 Location: Starkville, MS Posts: 63	Coductivity-based ATO? Please share your experience. Hello all, I am trying to get a sense for how reliable is to regulate my ATO based on the conductivity probe reading. Any thoughts? Please share...

06/02/2014, 05:01 PM	#3
aquamanic WHO DAT?? Join Date: Sep 2009 Location: Baton Rouge, LA Posts: 5,709	I don't think it would be a reliable method at all. I don't know how big your system is but it takes a lot of RO water to move the needle. If you had a system with 100g in it at a PPT of 35 and lost 5 gallons, the PPT would only move to 36.8. These conductivity probes only have an accuracy of +/- 1 PPT. So your 35 PPT system could read 34 or 36 and be within the accuracy of the probe. Now you've lost 5 gallons of water and your PPT only moved .8 PPT outside the accuracy of the probe. And that's a lot of water to replace at one time. Most people like to put in ounces at a time to avoid fluctuations. I wouldn't do it. I'd use floats instead. Way more precise IMO. __________________ I don't work for Neptune. Please put all questions into forum posts and not PM's. Visit the Neptune Community Forums for the latest Neptune updates - forum.neptunesystems.com

06/03/2014, 06:15 PM	#6
kenargo Premium Member Join Date: Jan 2007 Location: Redmond, WA Posts: 8,151	Don't do it! Yes, a conductivity probe is a good tool for monitoring but not nearly accurate enough to use as a method to replace water and control salinity mix in a live environment. __________________ Click on my name to visit my homepage and access a collection of AquaController and Apex software, tips, trick and other Q&A including a link to the 'unofficial Apex new users guide' with loads of helpful information and don't forget to put a pin in my location map. Current Tank Info: 225G, BK 300 Deluxe, Deltec PF601, Precision Marine Kalkreactor, 2-LMIII+6 pumps, SpectraPure UHE, Apex, LunarSim, Tunze 6305s. Mixed reef, clam, fish, etc.

06/02/2014, 04:39 PM	#2
Mark Bianco In Memoriam Join Date: Nov 2011 Location: Infinity and Beyond Posts: 2,445	Are you referring to the salinity probe?

06/03/2014, 03:50 PM	#4
wwanthony Premium Member Join Date: Sep 2003 Location: Huntington Beach, CA Posts: 417	In addition there is also a Temp element to the Cond readings. I would not do it.

06/03/2014, 04:23 PM	#5
Reefvet Registered Member Join Date: Apr 2003 Location: Southern California Posts: 1,941	The idea comes up every few weeks after someone has seen this video.