If the kitchen sink does not have a garbage disposal, you will want to avoid allowing any solid food material at all down the drain. Without a disposal to break it up, material such as carrot peels or other vegetable trimmings can quickly form a blockage—frequently out of reach of any tool.

Even if you have a garbage disposal, you should still avoid putting greasy or fatty food remains down the sink. These substances can coat walls of pipes and build up. Also avoid gritty, absorbent materials. Coffee grounds, pasta, rice, and similar foods can all absorb water, swell, and get caught in the built up grease, forming cement that can be difficult to remove.

Don’t grind eggshells up and rinse them down. Because they are heavier than water, eggshells will always find some low place to build up and will eventually cause blocked or slow drains.

Just obey those simple rules, and you should keep your kitchen drains flowing free and fast.