Want to know how to feed a shark?
Then just ask Doncaster businessman Mark Wilson.
Mark has been turning his hand to creating fish food for over a decade, creating top of the range snap for underwater life ranged right the way from goldfish to the big sharks.
And it is proving to be a successful recipe.
Some of the biggest aquariums in the world are now using his products, and now the feed is a Doncaster product that is looking to crack the giant Chinese market.
Mark works for World Feeds, a factory based on and industrial estate at Coulman Street, Thorne.
He set up the company with South Yorkshire businessman Peter Kersh, a multilingual salesman who made his name with the Sheffield engineering firm Gripple.
Mark made his name after creating a clown fish hatchery after the film Finding Nemo had made the creatures popular. which he later sold on. He later put his mind to fish nutrition, taking a scientific approach, and sourcing ingredients.
In 2004, Mark met Peter through the Department for International Trade, when he was looking to export his food. He travelled with Mark when he was taking his product around potential customers, and was convinced from their reaction to join the business, of which is is now managing director.
Since then the business has gone from strength to strength.
It now employs 21 people and export to 40 countries. Its customers include dozens of Sea Life aquariums around the world, and other public aquariums, including one of the most famous in the world, at shopping centre in Dubai. They provide top of the range own-brand food for Pets at Home.
The deal with Dubai was a major breakthrough for World Feeds. The now ship 10 tonnes of food pellets to the site, which is the biggest single aquarium customer. It used the firm's product to build up its stocks when it first opened, and it was a boost to World Feeds' reputation internationally
Last year they set up a deal with a distributor in China, after setting up a relationship at a major Chinese trade show in Shanghai.
And on top of that, the firm is looking at breaking in to the salmon farms market, with feeds for important stages of the lifecycle of a salmon.
But the growing demand means the firm is now looking for upscale its production.
It is currently in the process of developing new, bigger machines which will allow it to increase the amount of feed it makes, using its own in-house design team. Local engineering firms will be building the machines to the company's own designs.
Peter said: "We have investment from Finance Yorkshire currently. We want to stay here at Coulman Street, and if we do need bigger premises we will be looking for something in the same area. We want minimum disruption so we can continue to develop. We want to stay in Doncaster, here on the M18 corridor.
"We are looking to build capacity and volumes. That means bringing in more automation, and needing to developing into a bigger site, and it would mean we could get more through the factory.
The product is Defra approved, and Peter says one of its biggest advantages is that it means there is less waste matter from the fish to be filtered out of the water - because there is less in the food that the fish cannot absorb as nutrients.
The feeds are made of powdered squid, krill, and mussel, as well as fish meal as a protein sourse. For the herbivores, it uses natural marine algae.
They are then created into flakes or pellets, with different products for fresh water fish or sea fish; and for carnivores, omnivores or herbvores.
The food is also used to feed sharks - but they need some encouragement.
"As the fish's mouth gets bigger, they need bigger pellets," said Peter. "With some of the bigger sharks, we have done a lot of testing and research. They will bite, but if the texture is not right, they spit the food out again. What we do now is to take a squid, remove the insides, and fill it with a continuous strand of fish food. It means if feels right to the shark."
The only cloud on the horizon for the firm is Brexit. Peter is concerned about how leaving the EU may affect trade with Europe, as it could mean more forms have to be filled in, potentially putting up their costs.
"We are concerned there may be extra costs and delays," he said.
But he is pleased with the boost selling to China may bring.
He said: "We're pleased we've been able to develop a new relationship with China during the last year, because our brand name and reputation had people coming to us. We have had a lot of approaches in China.
"It's a big market - that's why we're looking to expand."