Something you don't need to know about me — but I'm going to tell you anyway — is that I spend a lot of timing shopping online, mostly for clothes and beauty products. While reading reviews about this $9 Aztec Secret Clay Mask that supposedly works miracles for your skin, one caveat kept bubbling up — and it was a big one: Don't wash it down the sink. Apparently, you should probably start washing your face with a hose outside, or using a filter in your sink, so it doesn't clog up. That was enough to deter me from trying it myself (yes, I am that lazy).

So I didn't buy the mask, but I did start wondering, is it just this mask that can clog your sink, or is it all face masks? What other beauty products shouldn't go down the drain?!

I spoke with John Wood, President of Hub Plumbing & Mechanical in New York City, to get some answers. Here's what I found out.

In the bathroom...

1. Face masks

So, my suspicions were right. Pretty much all clay and mud masks are a no-no for the drain. I've read that you can line your sink with paper towels to catch any residue as you wash the mask off, but John thinks this is actually a bad idea, as the paper towel could break apart and — you guessed it — cause a clog. Instead, he suggests using a fine mesh screen or cloth.

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Mrs. Doubtfire/20th Century Fox

2. Gels, soaps, and jellies

Think of the pipe in your sink like an artery: If you fill it up with fats, it'll clog. "The more gooey and luxurious they are, the worse they are for the drain. They accumulate in the trap under the drain," says John.

3. Bath bombs

Speaking of the tub, those bath bombs that are really great for Instagram are really terrible for the drain. (Fanatics swear by using a fine mesh drain strainer to prevent clogs, like John suggested.) Anything powder-based will cause trouble, unfortunately. Good thing no one uses Calgon anymore.

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puhimec//Getty Images

4. Hair

You should know this one by now, but I'm putting it in here as a big, fat reminder. Your hair will wash down the sink and the tub, and it will get tangled and create a clog. Make sure to buy a drain protector to catch as much of it as possible.

In the Kitchen...

5. Coffee grounds

According to John, washing coffee grounds down the sink is like "pouring sand down the drain." It's pretty much guaranteed that your sink will be full of water and take forever to empty if you do this, so don't!

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6. Boiling water

Be careful when you're straining pasta: Any water over 140ºF shouldn't go in your sink. John explained that in some cases, especially in suburban areas, building piping is connected to the sink by plastic, tubular pipes. If the plastic melts it could cause a whole lot of problems, like a flooded cabinet, damaged flooring, or even an insurance claim. And yes, repairing all of these things would get pretty expensive.

7. Grease

Remember when I said to think of your sink pipe like an artery? That rule applies in the kitchen, too. Any grease or fats from cooking will clog up your sink, so definitely don't rinse any pots or pans until you've drained the grease.

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Grease/Paramount Pictures/Giphy
Erm, not that kind of Grease.

8. Food

Go ahead, call me Captain Obvious, but you've got to stop putting food down the drain. During our phone call, John stressed that food should never go in the sink, unless you have a garbage disposal. Even then, he warns not to dump all of your leftovers down there at once. Add the food in small intervals, he suggests, and listen to the disposal. Wait until it's clear before you spoon more in.

Lastly, John says to chase everything you wash down your sink with cold water. Roger that.

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