Most of us associate fish in aquaria with neon, guppies or swordtails, which are widely available in pet shops. We are enchanted by the colourful sea fish we saw in the fairy tale “Where’s Nemo?”, and few people know that the royal pufferfish (Dory’s fish) is very fond of eating bananas – this is their delicacy, and in the wild we most often meet pufferfish near islands where banana trees grow.
Clownfish (Nemo fish), on the other hand, are able to change their sex during their lives. All clownfish are born as males and only when they grow up can they change their sex.
Among the aquarium inhabitants, we can also find sharks, which are the only fish that have eyelids. Another thing that characterises sharks is the lack of an air bladder to keep them afloat and so they have to swim all the time or rest on the bottom.