[header] How to lessen aggressive behavior in poison dart frogs [title] Note the signs of aggression. [step] If you have more than one frog in the terrarium, watch carefully for signs of aggression. These can include chasing one another and wrestling. 
Sometimes one frog will sit on top of another, preventing the one underneath from moving. It might look funny to you as an observer but it is highly distressing to both the attacking frog and the attacked frog to be worked up into such a state.