I have some BGJD that I am going to be putting into a tank with some other BGJD in hopes of breeding. My concern is that I am not going to be able to tell them apart once they are in together for awhile. I dont want to mix them up and accidentally inbreed when I remove them and put them in with others in the future. How do you all tell which fish is which when you have some that are VERY similar? Thanks.