Forget murky tanks with faux bridges, forlorn goldfish and a few fronds of seaweed floating in the gloom: today’s radical new designs feature living coral reefs, lighting to suit your individual colour palette, LCD screens behind the tank, brushed aluminium or stainless-steel finishes and shoals of fish — often of a single species — that make endless patterns, like flocks of starling.

“Design has come a long way, both in terms of the materials used and the ability to hide equipment,” says Matthew Bubear, managing director of Designer Aquariums, a West Sussex-based firm. “They are now much more sleek. Basically, aquariums are sexy.”

The vogue is for aquatic room-dividers, often separating an en-suite shower, for example, from the rest of a bathroom or from the bedroom. Or they can be used to introduce light from another room into a dark space. Think of them as glamorous alternatives to glass bricks.

Designer Aquariums recently installed a £180,000 aquarium in the home of a London publisher to separate the gym from the swimming pool. More modest arrangements are available from £1,500 to about £3,000.

Aquariums can also be used to fill difficult spaces. Matt Evans, an installation manager at London’s Aquatic Design Centre, has just fitted a cabinet with seahorses (costing £180 a pair) into an odd-shaped gap in a client’s wall. Room also had to be found for two tanks to house purified water and the live shrimps that seahorses feed on.

“The whole area looks striking now,” says Evans. And you needn’t know anything about fish to have an aquarium, either.

“Tanks are more advanced now,” he says, “so you don’t have to be an expert to stop your new housemates from floating to the surface. You can even pay someone else do the nitty-gritty things, like cleaning. But this comes at a price. Maintenance (which involves a twice-weekly service for coral reef aquariums), can set you back as much as £250 a month.”

But don’t let those figures put you off. A cheaper solution is a simple wall aquarium. Designer Aquariums offers an easily maintained version that is aimed specifically at the non-fish-expert. You don’t even have to get your hands wet when you change some of the water every week or so. Available in dark wood or aluminium finishes, a unit 725mm wide, 700mm tall and 130mm deep costs about £600.

Another option from Designer Aquariums is its simple 30-litre, 430mm-high round BB4 Fish Bowl at £99.95, which comes with halogen lighting, a filter kit, silver base and lid and start-up chemicals.

If you want something a little quirkier, it is possible to incorporate a fish tank into almost any piece of furniture, once it has been given a hidden steel frame strong enough to support the weight of the water.

Raoul Shah, founder and joint managing director of the brand marketing consultancy Exposure, has a tank housed in the top third of a £2,000, 8ft-high vintage French bar cabinet. “I love the way it brings life and colour to our home,” he says. “It gives the place an amazing light in the evenings, and when the sun shines through it, it’s like a prism, so the room is full of rainbows every morning.”

The customisation and Shah’s fish (which have ranged from sharks to parrot fish), cost £3,000. The pumps and filter system are hidden behind false drawers. “Guests always home in on it,” Shah says. “My three-year-old son and baby daughter love it, too. It’s a great way to get them to relax and calm down at the end of day.”

Shah’s tank is cleaned and serviced every six weeks, at an annual cost of about £1,500, which includes replacing the odd fish. “For a more interesting and beautiful picture, be daring with your tank,” says Shah. “I suggest you put it in a place, like a hallway, where everyone can enjoy it.” Especially the family cat.

Designer Aquariums, 08450 609 960, www.designeraquariums.co.uk; Aquatic Design Centre, 020 7630 6388, www.aquaticdesign.co.uk

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