safe age to seperate from mom

[Fisher]

My gerbil pups will be five weeks old on Friday.  Is it too early to separate them from their mom?  There was some pretty severe fighting between one of the 2 adult females and the sick baby this morning.  If I would have left the baby in she would be dead by now so I move all 3 babies to a separate tank.  At six weeks I was going to separate the 3 baby girls  into their own cage and leave the 2 adults together anyway.  Please give me your advice on this situation. Sara Fisher Steve ( hubby) Lauren (6) Steven (3) Baltimore, MD