heres a link to a great filter and not too high costs and easy to work with..and cheap replcement filters.

http://boards.cannabis.com/showthread.php?t=93372
wildchick Reviewed by wildchick on . Odor Problem Looking for an odor fixer for a room 5x8 room, but with no ventilation besides keeping the door open during "daylight". This unfortunately makes the rest of the house smell, but there's no way to install ventilation. Probably a lost cause, I know :P Rating: 5