You can find some plastic in a craft store or maybe a home-depot type place,
but might I suggest using driftwood? If you find some long pieces, you can
cut them to size to go across the whole tank, making a terrace. Put them in
the tank first, and fill in gravel around them, and they will stay put. Easy,
and works nice, especially if you plant java moss or java fern on them.

In article , "Jared"
wrote:
I'm planning on making terraces in the 20g tank that I'm going to get. I've
found aquarium grade silicon already, but what can I use as the terrace
walls? Is there anywhere I can find plastic strips to silicon to the
aquarium floor so they remain in place? I want to do this right, so any help
would be appreciated.
Jared



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"Insert witty comment here."
-John