ive caugt my tiger barbs at this a couple of times and will try to get a pic to show you but two of them keep locking lips and rubbing up against each other what are they doing
I've noticed my Green Barbs do that too every couple of weeks and can go on for hours...locking lips and rubbing against eash other as you say, I don't know if they are mating, or if it's two males fighting over the females...but sometimes they look a bit 'rough' after it