Parrotfish (Scaridae) are effective algae eaters for the reef, but some species will also live off rock corals.
Many of these fish will grow too big for most domestic aquaria, although there are some exceptions.

Parrotfish will generally eat a lot and often, which must be taken into account.
It is an advantage to have lots of algae in the aquarium which they can graze on. 

These fish will sleep in a mucus cocoon between stones. 

The species most often seen in tanks is Scarus quoyi, which is suitable for coral aquaria. It does have a large appetite, so the aquarium must have good filtration. 

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