Two Cent's Worth:

I use a 'Non-Stick Safe' scrubbie sponge (like you would use to wash your non-stick cookwear) along with "SoftScrub with Bleach". I've never had any ill effects from the cleanser (which I use very little of). It hadn't harmed my liner over the past 5 openings, and does a great job of getting the coping a nice bright white!

I tried the magic eraser last year, but you have to remember that the magic eraser does have the potential to remove the finish on your liner or coping. Magic Eraser uses Basotect (a melamine derived proprietary foam product - hence the concern about poison). I was worried about the abrasive nature of the magic eraser (not any poison issues) so I quit using it except on my steps. If you have plastic steps, it does a wonderful job of cleaning them without using any cleaning chemicals.

Good luck and enjoy your 2nd season!