I cant tell you how many times i have said about mixing herps, but tortoises eat poop its a fact. Your hermans will the russians or vice versa, The bacteria that live in each tortioses are quite different, This could cause all your tortoises to become ill and even die. Are you sure you want to mix them? The only tortoises that you can mix are red foots and yellow foots because they feed on the same things and have overlapping habititats. Also the burmese browns and blacks can be housed together. Please take my advice you will have happier tortoises