I have heard about the head bobbing thing but had never seen my guy do it until the other day ... it realy freaked me out seeing this - he has been doing it constantly for the past few days and his beard turns real black as he does it also he bobs realy fast and hard - almost like his whole body moves with each bob.
I have read this is normal but why all of a sudden now when he has never done this before!
We do have a new baby girl in another tank close to him but not right beside him ... i guess he could see her from across the room ... do you think this could be why he is doing it? We have had her about 2 weeks now.
Our male is about 9 months old and the new female is about 4 months.
It can be a problem. If she can see him it will cause her stress. If he can see her he may slow his eating. you best bet is to make sure that they can not see each other.
Id say its highly likely to be your new girl thats made him discover his hormones.
Just position their vivs so that they cannot see eachother, and try not to handle each of them infront of the others viv and he will settle down.