Calibrating a BeerBug is not hard.
My initial readout (it should be at right around 1 in water):

first find a tall slender container, a beer thief would be a good choice, but i just broke mine so used a vase.
Take a reading with a hydrometer in plain water
find the Cal 1 screen by pressing the button to the left
enter the value from the hydrometer by pressing the button for one second (it will long beep)
now add a couple of cups of sugar to the water and take another reading with the hydrometer and enter the value into Cal 2
It’s best to have a sizable difference between the first and second number, i may have gone a bit over board.
I then mixed half of my sugar water with pure water and took readings again to test.



