A large clear plastic storage container. This can be purchased in a hardware shop
Water plants such as Canadian pond weed, duckweed, water starwort, water milfoil and arrowhead
Horticultural sand and some gravel
Pond creatures such as, water snails, whirligig beetles, leeches, water lice, water fleas, water spiders, pond skaters, water boatmen, tadpoles.
Some smooth river stones
Using a Plastic Container to make
A Water Ecology Tank
A water ecology tank can be an endless source of interest for observers. It is an ideal apparatus for studying water creatures, food chains and for understanding the roles of carnivores, herbivores and detritivores or scavengers.
Setting up the Ecology Tank
Wash the sand and gravel thoroughly, before putting them into the tank.
Place about 3 cm of gravel in the bottom with about 2 cm of sand on top.
Use rainwater to fill the tank to within 8 cm of the top. (Pour it onto a piece of stiff cardboard to avoid disturbing the sand). If rainwater is unavailable use tap water that has been left standing for a week.
Add half a standard jar of mud from an existing pond. This will contain the eggs of water creatures and will also provide nutrients for plants.
Make sure the tank contains water snails. Snails keep the sides free of algae and water lice scavenge the bottom. Freshwater shrimp will do this as well.
Add a very small quantity of Canadian pond weed, an arrowhead and some duckweed.
Place the stones around the roots of the arrowhead to keep it stable. Alternatively it could be planted in a small pot.
Fork out the contents into a 1 cm mesh sieve and shake them over the barrow. Coarse undigested material will be left in the middle of the sieve. Put this into a plastic sack. It will form the basis of a new wormery. Leave about 5 cm of material in the bin. This will contain eggs. Empty the coarse material from the sack into the wormery.
Place the tank in good light but not in direct sunshine.
Water beetles, dragonfly larvae and water boatmen are carnivores. These should be removed after a short while, especially if tadpoles are being reared in the tank.
Dead plants and animals should be removed.
If the tank water gets dirty some of it can be siphoned off with the plastic tubing and fresh water added.
N.B. You may need to use a perforated lid, if you have tadpoles in the tank.
Bugs (Magazine Series).Orbis Publishing, London, 1994
Elsie Proctor: Looking at Nature. . A. and C. Black 1969
Andrew Mitchell: The Young Naturalist Usborne Publishing Ltd., London, 1989
Romola Showell: Learning About Insects And Small Animals Ladybird Books Ltd., Loughborough 1972