Acid spills can cause a chemical change to the colour of the carpet, or the strength of the fibres, and can even disolve fibres completley or cause it to seperate from the backing.
For this reason spillages of any acidic products, such as drain cleaner, vinegar (or worse), need to be cleaned up as soon as possible in order to avoid permanent staining and damage.

Your first step should be to absorb whatever you can with a dry white towel. Do not scrub, as you want to avoid pushing the spill deeper into the fibers or backing.

Next, you want to dilute and neutralise the acid with an alkaline/base substance - something common around the house you can use is baking soda mixed with soda water, (or regular water if not available). The stronger the acid, the more alkaline the mix must be - (a common spill such as vinegar is only mildly acidic).

next, you should apply a solution of ammonia (commonly found in cleaning products) diluted in water (one part ammonia to 10 parts water). **Don't go overboard on the ammonia as it can bleach your carpet if its too strong and left for too long!

Blot as much of this solution from your carpet as possible, rinse again with plain COLD water, Blot, rinse, Blot, Rinse until you are satisfied that the original spill has been completely absorbed/diluted.

Allow the area to dry off completely, and then vacuum it gently.

If you have left an acid stain for too long, and it has caused chemical alteration, there may not be much you can do to reverse it. In some instances, your Go Clean technician may be able pull something out of his bag of tricks, but the best thing to do is to treat it straight away.

If in Doubt, call your local Go Clean technician on 1300-1400-46 for advice or availability as soon as you are aware of the spill.