I bought some eggcrate to use as a lid for the 135, so the eels can't get out. They like to squeeze into small openings so no open top for me. My question is should I use what I bought to line the bottom of the tank with, so the rocks aren't sitting on the bottom of the tank? Then just put the sand on top of the eggcrate... The 135 is an AGA, so I was thinking it might be wise... Let me know...