Clownfish suddenly acting very aggressive

[dsaundry]

Your clowns are probably setting up to breed. They are establishing territory and any fish they deem a threat will be chased off. I have a maroon clown in a 90g and it is in with a trigger, purple tang, and even though it is the smallest fish in the tank, there is no doubt who the boss is. Its his tank and he protects his anemones fearlessly..You may find it settles down if there are lots of hiding spots in the tank, if not you may find a dead fish one day.