On 31 Dec 2005 04:34:14 -0800, wrote:

I have recently seen the sulphuric acid to clear blocked drains.
Having googled around, it seems I should not mix the 2. I am trying
the caustic soda today followed by boiling water and detergent.

If that fails, how long should I wait before i move on to the acid?

In future, tip a cup of soda crystals down the plug hole, followed by
a pint of boiling water. Repeat this every week of so and it keeps the
drains clear.

sponix