Backyard Aquaponics
A place to discuss aquaponics

Anyone interested in further information on a DIY PH sensor I have working for around $70 Aussie Dollars?

Using Arduino Uno (Think it was $25)
$26 sensor
$10 plastic box
$7 LCD screen

Hacked some Python and have it running for about a month now. Works a treat.

LCD displays voltage and PH and flashes up the reading after each test (tests in around 3 second intervals)

Photo below (ignore the funny characters at the end of the PH reading. Getting rid of that is way beyond my python knowledge) - but hey its accurate.

Nice work.

How often do you have to calibrate the pH sensor in standard solutions?

Ill drop the sensor into some neutral 7 PH and see if it reads correctly. Its been about a month and I've been keeping a close eye on it and from what I have seen Id say it will still be accurate.

Good job Kaiser .

Which probe are you using for $26. That's way cheaper than anything I've ever seen.

The garbage characters are Line Feed. The LCD doesn't know how to interpret those in it's character set. Use Carriage Return instead.

Here is the sensor I used

http://dfrobot.com/wiki/index.php/PH_meter(SKU:_SEN0161)

Its now $29.50. Gone up in price a bit.

http://www.dfrobot.com/index.php?route= ... vB6FtJ97IW

Use the supplied python script and added another part to get the LCD to work and flash the appropriate values.

So far 1 month half submerged and working well.

Oh boy would I love one.

If I could put a couple of sensors at the same time, that would be amazing.

Unfortunately I've never touched the arduinos before, might take a bit of stuff around haha

Sent from my SM-G920I using Tapatalk

Recently tested and running perfectly after about 2 months

After about a year later, I am curious to find out how well things have been working for you. I am also wondering if you leave the probe in your tank and perform fairly continuous readings, or if you just drop it in when you want to check the pH. I ask because I am interested in putting together some automation and data collection which would best benefit from long-term submersion/use, but I am not sure how well these sensors would hold up with this type of long term exposure.

As a side note, I also am a little worried about led content from the electronics in these inexpensive sensors. I have found more expensive ones (~$100-$200 USD) like the Sensorex S651CD which seem to be entirely enclosed and designed for long-term submersion, but it's hard to justify especially if the low-cost ones are good enough and at least claim to be led free.

Any information would be appreciated. =)

If you go the dfrobot link it actually suggest another "industrial" probe for permanent immersion.

https://www.dfrobot.com/index.php?route ... ption=true