Hey all,

Got my hands on a Gravity SEN0161-V2. After a lot of troubleshooting I cant seem to get a stable reading. If I use the included screw bottle with either 4PH or 7PH calibrating solutions I can get an almost accurate reading with only .04 movement of PH ( example 7.00ph - 7.04ph )

When I put the sensor in anything else such as a small cup of water or my aquarium the PH jump up and down erraticaly, for instance if I put the sensor in my 11 Litre aquarium my PH reading jumps between 6.4 - 7.8PH constatly. I am using the standard code included with the sensor and seem to have no luck.

The larger the body of water the larger the fluctuation in the reading.

Steps I have tried to resolve the issue.

1 Change between multple arduino's boards.

2 Change power input methods and different power supplies.

3 Test reference voltage coming into the Gravity sensor and the voltage is stable.

4 Let the PH probe rest in water for a long period of time to let it try stable out.

5. Eliminated possible interferance such as heaters and pumps inside the aquarium.

6 Recalibated the sensor multiple times on different hardware ( 2 point calibartion 4PH first, then 7PH )

A screeshot of my reading when putting the probe in my aquarium

After purchasing a cheaper almost indentical unit off ebay and it coming dead on arrival im starting to feel like these sensors are a gimic and dont actually provide a accurate reading, or am I just unlucky?

Any help would be appreciated :)

Thankyou