That is odd. It works perfectly for me and my room.

Did you cut out the middle of the plastic covering to get the most air circulation? I did that on recommendation of mcavana?

Because ever since I installed the frebreze filter my rat room/snake room hasnt stunk one bit. I have 4 breeding groups of 1.4 and a full 20 gallon long filled with weeners plus the snakes. 2 racks full...