Rabbit fish (siganidae) are known for being effective algae eaters.
These fish are often used to fight bubble algae, which can otherwise be hard to remove.
It can be challenging to keep them well fed, if there is not sufficient algae in the aquarium.
They all have toxic spines on their backs, therefore be cautious, although they will mostly swim away and hide, when your hands are in the aquarium. If these fish feel threatened they will hide next to a rock and change colour and pattern. They can appear "ill", but this is their natural camouflage
These fish are not suitable for small aquaria, as they can end up swimming around in the same circle all day long.