Non-toxic play sand should be okay for both cories and other fish. It is very attractive In My Opinion, easy to clean once in the tank, and is safe for fish, I would commend the plain colored sand. Dyed ones can leak harmful components into the water.
Playsand is very dusty when bought so ideally you would want to wash it very well. When I purchase new playsand I place a bit more than needed amount of playsand into a bucket, and continually wash out the bucket, refill, empty, refill empty, refill, Empty, refill, empty. Repeat this process until the water is virtually clear after 1-2 seconds of settling.
Good plants are hornwort, anacharis, anubias, amazon swords, dwarf chain swords, Hygrophila corymbosa, cabomba caroliniana, ludwigia Repens, duckweed, Rotala indica, Rotala Rotundifolia, and frogbit. Each have very low requirements.
I do have a written thread as a sticky on the top of this sub forum for any more help of care. I have articles on many plants that do not require soil, sand, or any substrate and floating plants
Last edited by Mo; 05-15-2012 at 08:20 PM.