New pet (also old)

Well i will start with the old pet (still current) , he is a male Betta and his name is Lincon. He is a beautifull fish, he has a light blue body with a sea green stripe that floods into the beging of his tail, his face is constantly black.
He is the mellow type he never shows agressiveness and he is lazy.
My new pet that I have had for three days is Sammy. Sammy is a beautifull black coat a black so intense that he blends into things, his eyes are a beautifull pearly black, and his tail is blackish greyish with a pink tip.
I need tips for mice, ecspecially homemade mice mixes. :D