How to unblock a drain at home (kitchen, bathroom and outside)

First, work out what's blocking it

• Kitchen sink: cooking fat that has set inside the pipe, plus food waste.
• Bathroom basin and shower: hair bound together with soap scum.
• Toilet: usually a physical object or too much paper — do not pour acid on a full toilet blockage.
• Outside gully: leaves, sand and grease from the kitchen line.
• Whole house draining slowly at once: that's a main line problem — call a plumber, not a drain cleaner.

Step-by-step: clearing a blocked drain

1. Bail out standing water so the product reaches the blockage instead of being diluted.
2. Remove and clean the strainer, and pull out any visible hair with a hook or wire.
3. Put on gloves and eye protection, and open a window.
4. Pour Gosh Pit & Drain Acid Flush slowly down the drain, following the dosage on the bottle. Pour, don't splash.
5. Leave it to work for 20–30 minutes without running water.
6. Flush through with a steady stream of cold water for two minutes.
7. If it's still slow, repeat once. If a second dose doesn't move it, the blockage is physical — call a plumber.

Critical safety rules — acid is dangerous

• Acid can burn skin and eyes and damage lungs if fumes are inhaled. Treat it with respect every time.
• Never mix an acid drain cleaner with bleach, ammonia or any other drain product — the reaction releases dangerous gas.
• Always wear gloves and eye protection, work in a ventilated area, and keep your face away from the drain opening.
• Never use acid flush on a blocked toilet full of water, or where a plunger has just been used.
• Keep it sealed, upright and out of reach of children and pets.
• If it splashes on skin or in eyes, rinse under running water for at least 15 minutes and seek medical help.

Stop the next blockage

• Pour cooking fat into a tin, not the sink.
• Fit a hair trap in the shower and basin.
• Flush kitchen drains monthly with a maintenance dose.
• Run hot water for 30 seconds after washing greasy dishes.