Cape Breton University 1 article published in JoVE Biology Silencing the Spark: CRISPR/Cas9 Genome Editing in Weakly Electric Fish Savvas J. Constantinou1, Linh Nguyen2, Frank Kirschbaum2, Vielka L. Salazar3, Jason R. Gallant1 1Department of Integrative Biology, Michigan State University, 2Faculty of Life Sciences, Unit of Biology and Ecology of Fishes, Humboldt University, 3Department of Biology, Cape Breton University Here, a protocol is presented to produce and rear CRISPR/Cas9 genome knockout electric fish. Outlined in detail are the required molecular biology, breeding, and husbandry requirements for both a gymnotiform and a mormyrid, and injection techniques to produce Cas9-induced indel F0 larvae.