Agroup of Hong Kong hobbyists are brightening up their fish tanks with creative landscaping.
The aquarium lovers have set up Creative Aquascape Union (CAU), which has weekly meetings and a bilingual website - cau-aqua.net - on which they share photos of their aquarium creations and exchange ideas about taking care of aquatic plants
Dave Chow Wai-sun, winner of the International Aquatic Plants Layout Contest in Japan last year, is one of the association's most active members. Mr Chow has turned his hobby into a business - he owns an aquarium shop in Tung Choi Street in Mong Kok.
He says beginners can start with basic fittings such as the aquarium tank, a filter, gravel and soil, along with UV lights, which altogether cost less than HK$500.
But in order to maintain a complex ecology in the tank, 'aquascapists' need to spend considerably more - up to HK$30,000 for an advanced set-up.
'You need to install good-quality equipment, such as a chiller, to maintain a complex ecology in the tank, and that costs a lot,' Mr Chow says.
The hobby also requires a large amount of effort.
'To maintain a balanced and healthy ecology in the tank, you have to know the characteristics of different types of plants,' says Gary Wu Kwok-fai, another CAU member.
Different plants require different conditions in terms of water temperature, the type of soil, water acidity and light intensity.
'Most of us get our information on the internet,' says Harry Kwong King-man, who has four tanks at home. He says aquarium landscaping helps you develop patience. It takes several months for the plants to grow, and continuous effort to maintain the beauty of the aquascape afterwards through pruning, changing the water, and maintaining the right balance of light, nutrients and carbon dioxide.
Aquascaping enthusiast Justin Law Kai-chun says you do not need a lot of space to enjoy the hobby. He specialises in small tanks, up to 50cm in diagonal length.
Mr Law won the top prize in the 2005 and 2006 Aquatic Gardeners Association (AGA) International Aquascaping Contest, and was a judge for the US-based association at last year's contest.
If you want to start an underwater garden, check out the Goldfish Market in Mong Kok.