Conductivity Monitoring Recommendations


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I wanted to know if anyone has added Conductivity Monitoring to this project.  If so what probe and hardware was used to do this.  I have seen many options of connecting Raspberry Pi to hardware, but wanted to know if it is possible to add this as an input on the existing box and have it report values.  Any help would be great
Hi, currently it hasn't been added but some point I would like to integrate it through the back door so to speak. reef-pi has a file driver that will read a single value from a text file, with that it's possible to have a script running in background on Pi that's reading an EC circuit and writing it to file. In reef-pi you would bring this in through the pH tab so you would have the same features minus the calibration, that would need to be done with a separate script and saved to circuit. said:
are we talking about the salinity probe ?  ORP probe?
in any case, is the addition of a salinity probe would be in the same way as above ?
So i currently have this working wonderfully.  I have Salinity,  ORP, PH,  room temp/humidity and a few other items I run a script on another pi that gather this data and puts it into a file which I read every few mins in REEF-Pi and chart for current and history the results
There's really no limit what you can import into reef-pi, it's a pretty flexible program.
Soon I'm going to have some scripts available so it's easy to add EC, ORP, DO, flow meters, etc.

Now I'm thinking about adding a salinity probe to get that manual measurement off my back. Let's say I buy the Atlas Scientific Probe K 1.0; my question is, could I use your add-on Isolated pH Circuit to connect it? Or am I better off getting the Atlas Scientific Connectivity Kit which includes the circuit board? In any case I'll modify the reef-pi code to read the measurements directly and not use the file driver; it should behave similarly to the current pH capability. Please let me know, thanks!
Now this would be an update people would love, I get asked all the time, but yeah a little pricy, that's the main reason Ranjib hasn't supported it along with it not being open source.

Unfortunately my circuit won't read conductivity, apparently the circuits are similar but I think there are some differences and of course the code to calculate.

This is the circuit you would need, it works like the pH so you could basically copy and paste the pH driver and tweak for EC.

One nice thing about these circuits, they output conductivity, TDS, salinity and specific gravity if probe is in salt water.

Sadly Atlas makes you buy a 2nd board to isolate the circuit which is required, you need to choose which one to support as they now have a USB version.

We have this style of board, it uses I2C like my pH circuit and the other circuits compatible with reef-pi. If this was used the ezoPh driver in reef-pi is setup for I2C like this.

In the last year or so they brought out this carrier board which IMO is the way to go however you won't be able to use the ezoPh driver as a reference as this one communicates different. They do say it works with Raspberry Pi and provide some USB drivers however I've personally never used them so not sure how easy it is to work with, I2C is easy. The reason I like these is I2C was never designed to leave a PCB without being converted to a differential signal. If multiple external I2C devices are added it could/will bring troubles. Reef-pi already needs pca9685, pH, possibly RTC, possibly the SHT31 they added (should have been a DHT22), possibly the ADC they added and now possibly the EC. This is a lot of I2C devices, anyone doing DIY and wants all these will likely have issues as there will be too much cable/connections, it's really setting people up for trouble.
Thanks for the info Rob, I'll keep looking. There's some interesting and (relatively) inexpensive Chinese stuff on eBay.

I checked out the DFRobot offering; unfortunately the probe -- while relatively inexpensive -- is not rated for continued use under water. Will keep looking, thanks.
Ah that's stinks, they don't even offer the circuit without probe. I believe other analog circuits are very similar, as long as you have ADC they should work.

Rob, any movement on this in the past couple years? Any current roadblocks that need to be addressed? Do you need a probe / circuit yourself? How can I help jumpstart this? :p
Hi Blake, I think I'm getting close as someone is designing a circuit, he's actually waiting on me to put the circuit on a board now so final testing can be done. Maybe in a month or two I'll have it. This would definitely be a nice addition as I'm always asked about it.