Blue lagoon or creature from the black lagoon?

Cute little lagoons, pondless creek beds, bubbling boulders, and over flowing urns are all very popular ways to bring that tranquil sound of water into your landscape.  It too requires maintenance regularly to keep it looking tranquil, and not become a black lagoon. Light, warmth and debris create a great environment for algae to grow. A good cleaning in the spring should include removing sediment that collects on the bottom of your water feature as well as debris that blows in. Stone or pebble in the basin area should be pulled up and cleaned annually to bi-annually.  Washing all the surfaces in the water feature thoroughly will also help. The rest of the summer requires consistent regular maintenance including chemical treatments to keep the algae down and the pump/filtration system working efficiently. For more specific information talk to your local pond/water feature company, often they can test your water to give you a better assessment of the problems you are attacking.