buy one of theseinfernox wrote: ↑ Drano works very well for our washrooms (long hair clogs) Trick is to let the drain dry as much as possible. We shower at night so we put a little bit in the drain first thing in the morning, and after every 4-5 h to "recoat" the gunk. Then before showering at night, dump piping hot water. In extreme cases, you might have to repeat this twice.
No point in dumping the whole thing in the drain, use a little and let it coat the gunk. Water reducecs its effectiveness and give it time to do its work, its a chemical breakdown after all.