drano...what do I get here to unclog the tub?

our bathtub keeps clogging due to flatmate who doesn't clean out her damn hair.  I need to get us something to pour down it but I have no idea what to get as some products I have used in the past were terrible.  Back in the States I used the drano gel and it worked liked magic, what does everyone suggest I use here? Do they have drano here? Help, I am sick of standing in a tub of water while showering... EWWWWWW!

Mr. Muscle sink and plug drain might work, or we've used demestos which seems to work okay for us. 

Make sure when you use the Mr. Muscle or Drano equivilant, you follow it up with BOILING hot water from the kettle. This will help push the hair clog out and away.

Good luck

Bleach and a plunger is what I've always used. (I moult a lot).

1/2 cup baking soda, with 1/2 cup vinegar (watch the science fair volcano errupt) followed by a kettleful of boilig water

Plus, you can get those little hair catchers to put in the drain to help keep it from happening again.  Your roommate still might not empty it, but at least there's less of a chance that it goes down the drain before someone can get to it.

Ours works a charm as long as I remember to put it in.  My husband always takes it out before his shower.

1/2 cup baking soda, with 1/2 cup vinegar (watch the science fair volcano errupt) followed by a kettleful of boilig water

This is the best to watch!  And ecologically friendly.