I know when mine first reached maturity this is what they did, non-stop, the males would even hug each other which I can only assume is their way of competing for who gets to fertilize the eggs? anyways, now I can notice the female slowly getting bloated and the males start "singing" which indicates some babies are on the way and they will hug the female around this time. I was worried at first too until I noticed one day eggs all over the tank and the hugging stopped. Keep an eye out, maybe you will have some eggs on the way or maybe they are just getting prepared? That is about all the input I have on the subject, not sure what else it could be, just thought I would throw my 2 cents out there in case it helps