I have a question on rats. Are they less aggressive to each other than mice? I ask because, I have only one male and 5 females. Three females were given to me and are housed seperately from the male and 2 females. One gave birth right after I got her and the babies are 2 weeks old.

So... can I eventually move the male between the 2 tanks, or, should I find another male? Or, if I get them a big enough home-- right now they are in 55 tanks, but looking for something bigger-- can I move them all in together? I guess my question is, do rats kill newcomers or welcome them with open arms??