No one ever said sleeping with the fishes would be easy. Under sea hotels have long been a dream of architects, travellers and futurists alike, but the process of making them a reality has hit some rough waters.

Dubai’s Hydropolis, located 20m under the Persian Gulf, was set to be the world’s first underwater resort, but the global recession put the project on hold indefinitely. Fiji’s 24-room Poseidon Undersea Resort was slated to open in 2008, but has been delayed multiple times and now expects to open in late 2012.

Of the underwater operations that are still afloat, the most successful have been small ventures, offering only a room or two and somewhat minimal amenities. Jules Undersea Lodge in Key Largo, Florida has been open since the 1980s and requires guests to scuba dive 21ft below the surface to reach a 600sqft living space in the middle of a protected lagoon. The nightly fee ($500 to $600 per person) includes dive gear, diving access to the lagoon and dinner served in the lodge.

Owners of the Utter Inn in Vasteras, Sweden sail to the middle of Lake Malaren to drop their guests at a floating barge topped with a modest red entrance structure. Travellers descend a ladder to get to their room, 3m below deck. They also have access to an inflatable canoe for above-water excursions. Rates start at 12,000 krona per week.

The most luxurious underwater room option transforms the Ithaa underwater restaurant in the Maldives into a private bedroom ($11,710 per night), including a private champagne dinner and breakfast in bed. The resort needs 14 days advance notice to book it as a suite.