The baking soda and a bucket fix

You will need

• Rubber gloves · Bunnings or Woolies, ~$3–5 a pair
• Old towel or rag · Any old cloth you have at home
• Small bucket or large bowl · Something that fits under your sink cabinet
• Baking soda (bicarb soda) · Woolies or Coles home brand, ~$1.50 for a box
• White vinegar · Woolies or Coles, ~$2 for a 2L bottle — use separately, never mixed with bleach
• Old toothbrush · Spare one from the bathroom drawer

Step 1

Clear under the sink and pop on your gloves

Pull everything out from under your sink cabinet so you have room to move. Lay the old towel down to catch drips. Put your gloves on before you touch anything.

Step 2

Put the bucket under the bottle trap

The bottle trap is the round cylinder-shaped bit of pipe directly under your plughole. Slide your bucket directly beneath it to catch the water that's sitting inside.

Step 3

Unscrew the bottle trap by hand

Most bottle traps are plastic and unscrew by hand — just twist the round body anti-clockwise. Don't force it; if it won't budge, use a rubber jar-opener for grip, not metal pliers. Water will drain into your bucket as it comes loose.

Step 4

Empty, then scrub with bicarb and an old toothbrush

Tip the gunky water into the bucket and shake out any built-up gunk (hair, soap scum — it's grim, this is normal). Sprinkle bicarb soda inside the bottle trap and scrub every surface with the old toothbrush. Rinse it clean under a tap.

Step 5

Pour white vinegar down the drain pipe while it's off

With the bottle trap still removed, slowly pour about half a cup of white vinegar directly into the open drain pipe in the wall. Let it sit for two minutes, then flush with a full kettle of hot (not boiling) water. This clears the gunk you can't reach by hand.

Step 6

Screw the bottle trap back on and test

Hand-tighten the bottle trap back on — firm but not forced, overtightening cracks plastic. Run the tap for 30 seconds and check under the sink for any drips. If it drips at the join, tighten just a quarter-turn more.

The stop point

If the pipe coming out of the wall is metal and corroded, cracked, or starts leaking from a joint you didn't touch → stop, you need a licensed plumber.

If that is where you are: public cost guides put a blocked drain job at $150 to $450 (sources: ServiceSeeking 2026 price guides; Airtasker cost guides (2024, handyman tier); captured 2026-07-12). See the full cost guide.

Mendy calls tradies for you. Your first booking is free, then $3.50 a booking.

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