Errgin? So few ways? I think that Exorcist Launcher, (Multi-)Meltas and Meltabombs is all you need!
They have Retributioners, Seraphim, Exorcist, Redemptionists(Zealots with powerfist equivalents) and LOADS of squads that can take Meltas(and of those Dominions arn't the least)...Yeah, and Dominions can take Meltabombs as well.
In short. The foremost weapons against tanks are Dominions, Seraphims, Exorcists and Retributioners. But no squad is completely without means to take out even the heaviest of tanks.
Their problem is that their means of annihilation are all shortranged except for the Exorcist so the main problem with SoBs is getting your guns into position.