There are many fish sold under the "Electric blue" name. If you could Identify what species you have and maybe post a pic some of us may be able to help you out.
But generally speaking female fish tend to be thicker around their abdomen and males tend to be a bit longer and leaner looking. Also male dorsal and anal fins tend to be more pointed and longer while females fins have a more rounded appearance.
Im going to guess they are Electric blue acara?
Welcome to MFK by the way.
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