This North American pondweed is widely recommended for demonstrating oxygen formation during photosynthesis. Elodea is cheap and easy to grow, but other pondweeds can also be used.

Practicals

• Photosynthesis -  Resources: Demonstrating oxygen formation during photosynthesis can be a tricky process. One common way is to gather bubbles of gas given off by an aquatic plant. 

Teaching Topics

• Photosynthesis and respiration

 Description

Canadian Pondweed, Elodea canadensis

A native aquatic plant of temperate areas of North America. A recorded pest on rivers and canals in the UK, particularly in the 19th century. Its distribution was aided by botanic gardens both in Britain and mainland Europe, and is now found widespread in all areas south of the Arctic, including Australia and New Zealand.

Growing and sourcing

Obtaining: Easily available from aquarium shops or pet shops that have aquarium section, and specialist science suppliers such as Blades Biological. A care sheet can be downloaded from them too. There are also species of Elodea available, some of which have been reclassified as Egeria.

Care: Blades Biological provide care information for Elodea . They also supply both plants. Elodea can be kept living in an aquarium long term if anchored with gravel it should then begin to grow. Short term it can be kept in a shallow tray covered with water. You can find more information about caring for pondweed in the video here.