I think the chemical you are referring to is Boyd's chemi-clean. Just search some place like marine depot for red slime remover. But make it a last resort because there have been reports of the stuff coming back stronger than ever and a bit resistant if you haven't done anything to also correct the problem.
And slightly OT, reefynewby, a refugium is not "a must for every sucessful reef." A lot of people use them successfully. Some people, like myself, don't. I think a lot of the BB folks don't use them either. And I definitely don't see my tank crashing anytime soon. Very few things in this hobby are an absolute "must."