lid construction

[karazy]

so i need to build a new lid as my fish are jumpers, and my glass lids block too much light.
ive been looking at making a lid like the one in the link added below, but i cannot for the life of me find the 1/4 or 1/2 inch plastic mesh used to make these lids anywhere.
everyone says home depot but i look and look and look and i cannot find it anywhere.
does anybody know where to get this mesh in calgary or have some extra they can spare, or have a better lid design?
http://img.photobucket.com/albums/v7...n/100_4666.jpg