I have a weekend off coming up and I've decided to move my midevil (was hoping he was a red devil) from his 55 gallon home to the new 90 gallon I recently received, and naturally I've begun to second guess myself. On deciding which substrate to use I haven't been able to pick one on my own so I was hoping some of you guys guys could offer your opinions, suggestions or recommendations to help me out. I've heard pool filter sand from one source, play sand, all purpose sand and pebbles from another...enlighten me.