Ive had two shocks from him and both on the day i bought him. The first was a mild jolt up my leg while he was in the bag on the way home in the car, my GF had to break hard which frightened him so he let me know
The second time was later that day when he was exploring hs new home and knocked the filter off the glass, i had to put my hand into the tank to pick the filter up off the sand and stick it back on the glass and he bolted me as my hand got near him
Since then he has been well behaved and doesnt mind me doing maintainance in the tank, he also loves to be hand fed and will stick his nose several inches out of the water to take the offered food