Fat, oil and grease (plumbers call it FOG) is the number one enemy of kitchen drains. It goes down as a warm liquid and turns back into a solid inside the pipe — usually a few metres along, where the pipe is cooler.
Hot water and dishwashing liquid only move the problem. They carry the fat a little further before it cools, congeals and coats the pipe walls. Each layer traps food particles, and the pipe diameter shrinks month by month until the sink drains slowly, smells, and finally blocks.
Habits that actually work:
- Wipe before washing. Paper-towel greasy pans and plates into the bin before they hit the sink.
- Collect used oil. Pour cooled cooking oil into a jar or the empty bottle it came from, and bin it.
- Use a sink strainer to catch food scraps — rice and coffee grounds are notorious for settling in fat layers.
- Run hot water for 20–30 seconds after washing up to keep the trap and near section clear.
If your kitchen drain is already slow and smelly, the grease layer is established and home remedies rarely shift it — bicarb-and-vinegar fizz is satisfying but cosmetic. A proper fix is jetting the line with hot high-pressure water, which strips the pipe walls back to bare, then keeping it clear with the habits above.