My Mandarin pair were doing this for a good 5 minutes. They were appear to be courting just prior to the male biting the female. I feel bad.. been trying to separate them since yesterday to no avail (my tank is too big). They're behaving normally now though.. just minor chasing, etc. They've been together in the tank for 2 years. This is the 1st time I've witnessed them behaving this way.
