Fung Shway – Feng Shui

the spider plant http://en.wikipedia.org/wiki/Chlorophytum_comosum
for a full list of filtering plants
http://en.wikipedia.org/wiki/List_of_air-filtering_plants
TOP 10 plants most effective in removing:

formaldehyde, benzene, and carbon monoxide from the air.

Common Name Scientific Name
Bamboo Palm Chamaedorea Seifritzii
Chinese Evergreen Aglaonema Modestum
English Ivy Hedera Helix
Gerbera Daisy Gerbera Jamesonii
Janet Craig Dracaena "Janet Craig"
Marginata Dracaena Marginata
Mass cane/Corn Plant Dracaena Massangeana
Mother-in-Law’s Tongue Sansevieria Laurentii
Pot Mum Chrysantheium morifolium
Peace Lily Spathiphyllum "Mauna Loa"
Warneckii Dracaena "Warneckii"
http://www.zone10.com/tech/NASA/Fyh.htm
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Cannabis
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no such thing in fengshui.

fengshui is about manipulation of the structures of our houses or its surroundings to enhance luck.

regarding plants, remember that though plants give off oxygen by day, they take in oxygen and give off carbon dioxide at night. and when you are sleeping, i think this can be a concern, esp if you are in the room with the plant.
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