Hi I have a 3 gallon cycled and heated tank with plants but I just got a 10 gallon tank. Do I have to buy another filter and let it cycle before I add my betta? I dont wanna put my betta through another cycle (I have a sponge filter in the 3 gallon tank). Is re-cycling this one my only option? I heard that once you cycle one tank you will never have to cycle another tank, how would I do that method? Is this method safe to add the betta to right away? Thank you.
PS: I am adding two african dwarf frogs to the 10 gallon with my betta. My betta flares at anything I put up to him (except my face). My fingers, any object he will flare at. Does this mean it is likely that he will be aggressive towards the fish. I know i will not know for sure until I try but is it more likely?