Electrophorus electricusas it happens there is a 2 page section in a book I am reading at the moment. Size 7.5 ft Quote An adult Electric eel can create an electric discharge of 500 volts powerful enough to stun a horse""These nocturnal fish seldom come out during daylight Now get this "Electric eels can be hand fed but with care!!!" I have kept some silly fish in my time (love a red snakehead etc) but one silly mistake could have you on your back if it can stun a horse then 
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