Mermaid Villa Aquarium Decor

• At most aquarium supply stores, you can find several mermaid figurines. To set up your mermaid villa, you'll need to choose a Mediterranean mission-style house structure, reminiscent of an Italian or Spanish villa. Use green aquarium rocks that look like grass and place mermaids strategically throughout the landscape, at home in their little villa.
  
  

Decorating Your Aquarium Like a Sunken Pirate Ship

• Sunken pirate ships are a popular decorating theme for aquariums. Since the pirate ships double as the fish's safety retreat, they're the first thing you should select, then get enough accessories and little pirates, treasure chests and skeletons to suit your fancy. Use black aquarium stones for a creepy look and white for a tropical island look.
  
  

Castle Ruins Aquarium Decorating

• For medieval European romance albeit underwater, choose a castle-ruins decorating theme. Start with your underwater castle shelter for the fish, then add other decorating elements, such as a re-purposed pirate's cannon to protect the castle from invaders and an overgrowth of plants and vines, reminiscent of sleeping beauty. Sometimes you can find Disney Princess fish tank figurines that would look right at home in your castle.
  
  

Water Garden Aquarium Theme

• Underwater plants are good for your fish, providing hiding places as well as oxygen and absorbing toxins and waste in the water. Create an underwater garden for your fish by lining the entire back of your tank with tall plants and placing a few smaller ones toward the front of the tank. Purchase plastic and resin versions of some aquatic plants as well as miniature resin garden benches, wheelbarrows and other gardening items. A little shed creates a nice protective structure. For pebbles, use green and brown or river rock.