I have read that EBJD X EBJD offspring are usually not viable and die off before they reach a sellable size. With that in mind, it is my opinion that you would be best off with a male EBJD and a female BGJD. EBJD's are less aggressive than their standard counterpart, and males are larger than females, therefor a male Jack would probably be too aggressive for a female electric blue. The size/aggression issues should even out fairly well this way. Also, wouldn't EBJD X BGJD result in [roughly] a 50/50 ratio of electric blue and blue gene offspring? I haven't done punnet squares since I was in middle school, but I believe if you worked it out on paper that is what you would get. Keep in mind, I am no expert on the subject so I cannot say with 100% certainty that what I am saying is fact, but I have however studied breeding electric blue's for roughly six months and this is what I have concluded.