Step to use the Doctor:
1. Plug in the power supply, make sure insert the reactor mesh cable firmly to the unit until you feel a ‘click’.
2. Open Bluetooth, GPS(for Androids) and Location Service. Search and connect the device in the app.
3. Enter device setting page, type actual water TDS in PPM that tested by a TDS Pen, then type your tank capacity in liters. Confirm it, ignore the pop out notification, back to the tank page.
4. The doctor will work automatically at a random time.
If your water TDS is high for your tank volume, you can change water to low it.
If you follow the above steps but still not work, you can use an Android phone to test.