DO NOT USE SEVEN ! Or for that matter diazanon . Both have been proven harmful . A better ( and organic solution ) thing to use is Diatomaceous Earth . It is a great thing to use for all soft body insects which include fleas . here is a link where I found some great info on it . I have not had the need for this great stuff for a long time . But recently have found the need for it again .
http://www.hydromall.com/happy_grower16.html . In some areas you may find this stuff hard to find . But thanks to the net you can find companies that carry it . Also my sister used seven at her house and the cats got sick from it . Yes it got rid of the fleas but it did get rid of some of her kittens as well .
Kevin