Andre wrote:

Go to the craft store and ask for plastic canvas. It has small holes
to allow water movement and will be easy to cut into any size.

I second that, though I wonder if the holes may be too big, and allow
the young to slip through. There may be a finer mesh variety available.

Anyhow, to the original poster, if you're not familiar with what Andre
is talking about, here are some photos of how I used this craft canvas
to divide a ten gallon tank:

http://www.ericschreiber.com/aquarium/tank3.html


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