Finding Nemo is the film every youngster wants to see.
Finding Nemo has been a hit film
And the stars of the show, clown fish, have now become the pet everybody wants to own.
But before children rush out and buy one, aquarium experts are warning them of the work involved in caring for such creatures.
Clowns are marine fish, making them the hardest of all fish to keep.
For a start, they require warm water (unlike goldfish which survive in cold water).
And unlike many tropical fish, such as guppies, clowns also require salt water with a similar chemical composition to the sea.
Pet store owner Nigel Bowler, from Critters Cabin in Nottingham, says demand for clown fish has increased since the release of Finding Nemo, as it did following the film's release in the US.
However he encourages youngsters to opt for something else.
He says: "Obviously it's a film aimed at children and, after they see the film, they would all like to live with Nemo.
"We are getting a lot of inquiries... but marine fish aren't necessarily suitable for young children.
"We are talking to the children and steering them into the idea of keeping a goldfish to start with and then progressing maybe in a year or two."
A clown fish which is not cared for on a daily basis would most likely "suffer and then die," Mr Bowler says.
"Nature has designed them to live in oceans which chemically do not change.
"In a small body of water in the home, you get chemical fluctuations which the fish can't tolerate."
A quick scan of aquarium magazine Practical Fishkeeping shows why clown fish are not suited to beginners.
Among other things, it recommends someone keeping clown fish purchases an aquarium measuring at least 90cm x 30cm x 38cm, a filtration system, a substrate of fine aragonite, a hydrometer to measure salinity and test kits for nitrate, nitrite, ammonia and pH.
- Live in anemones
- Reach about 80mm in length
- Native to Indo-Pacific region
Helen Kennedy, from The Aquatic Centre at Bulcote, just outside Nottingham, says many people have an attitude that fish are disposable.
She says: "Keeping a fish is entirely the same responsibility as a dog or a cat.
"If you don't want to put the time and effort into keeping marine fish then it's actually quite difficult and it's best not to bother."
Of course, it is perhaps a great irony that Finding Nemo is resulting in greater interest in fish as pets.
A main message of the film is against the idea of keeping fish in captivity.
However the clown fish on sale for £9.95 at The Aquatic Centre was not taken from the Great Barrier Reef like Nemo.
It was bred at a tropical fish centre in Hertfordshire, near the M25.