Rocking the AquaNerd Picture of the Week this go-around is the lovely symbiosis that all marine aquarists can recognize. It highlights the relationship between a clownfish and an anemone, which has become a staple in the hobby. The picture focuses on a clarkii clownfish (Amphiprion clarkii) and its host bubble tip anemone, which are seen at the Downtown Aquarium in Houston. The clownfish resides in the anemone, using it as a safe haven against predators, while the anemone benefits from regular direct feedings from the clown. The clownfish will defend its home fiercely, fighting off any other fish that venture close enough.