Topic Glyph of Purify on Tsulong?
It doesn't do 3% of his hp, but it does do a heal. The heal has a hard cap to prevent crazy exploits on bosses that modify tank health, but it will still heal tsulong. You should be glyphing for it and be the one dispelling tsulong for your raid team.
Here's the log of our most recent Tsulong kill showing the healing it did: http://www.worldoflogs.com/reports/y19zg5gv5gvp5j0h/spell/56131/?s=6232&e=6633