I was just about to take a shower in purpleglitter's apartment, and noticed there had been a minor back-up issue. Mostly dried, and not to bad. Nevertheless, a crust had formed over the drain, essentially sealing it. Not wanting to use anything that might pose a danger to the birds, I decided to use the remainder of the pseudomoonshine I purchased over the summer to clean the tub and unplug the drain. It worked like a charm, however now the house smells like I've just thrown a heavily alcohol-laden party. Ah, well - it will dissipate.