This is so weird!!!

Ive been reading this thread, and im in the exact situation!!

I brought my dumbo rats last friday (6th march) from pets at home and one is so laid back he lets you do anything to him, he loves cuddles and sitting on my shoulder and running up and down my arms and finally curls up in a ball and goes to sleep in my pocket. But the other is completly different! He bites me all the time ive been wearing a glove so i dont move my hand away when he bites and when i take off the glove he still my bites me. He will come up and sniff me when the cage door is open but as soon as i go to stroke him he runs away or bites me. Ive called pets at home about this as this is my first time owning rats this is also why ive joined this site and im gald i did now because pets ant homes response was well all rats are different you must if picked one with a hypo temperment?! hows that helping and advising me?!

Also if any1 could help me... The one that bites all the time (melvin) likes fighting with the laid back one (monty) and bites him all the time.. pets at home told me its because my cage isnt big enough but it cost me £120 and pets at home told me to buy it because its the best one for dumbo rats?? and its huge it has 3 levels and loads of toys and tubes e.t.c to keep them entertained. So could there be another reason why melvin feels the need to attack monty? bearing in mind hes been doing it since ive had them?? could it be that hes trying to show him whos boss, or top male?? any help or advise would be very very much appreshiated... x