Sapphiron guide.

http://www.tankspot.com/forums/f206/41969-naxxramas-sapphiron.html

Key things:

Move back and forth, side to side as the AOE is coming - Don't worry about DPS, the boss will still be there once you get back. Just move.

All need to be faster on getting to the ice blocks.

Don't stand together waiting for the ice blocks. Split up > Wait for the ice block > then group up. The damage done to the person ice blocked also hits everyone with 10 yrds.

Deadly Boss Mods has a feature which produces a small window on your screen which lists all players (and enemies?) within 10 yards of you. It can be very useful to ensure we don’t get damage from the ice block being cast on somebody next to us, and to not be too far away to hide behind the block once it has spawned.

good one ...