Seeing black sludge coming out of your sink drain can be quite a nightmare for anyone unfamiliar with it. But even so, it’s not uncommon. However, it's quite likely that the first time you run into this problem, it’s not the last. If you run into a black sludge problem in your sink or toilet, here's a quick guide on dealing with it.

What Causes Black Sink Drain Discharge?

The appearance of black sludge in your toilet, sink, or tub drain is caused by a few different things. Figuring out what the exact cause is will help you learn how to fix the issue. Here are some of the causes of black sludge in your drain:

Hair - Not all hair is bad, but if you have a lot of hair in your sink, you might be able to see black sludge in the drain that you probably don't want to see. If your drain is clogged with hair and you can't reach it with a plug or a plumber's snake, you're probably looking at having to call a plumber. After dealing with this issue, you may also consider investing in a drain hair catcher like our TubShroom products to prevent future buildups. 

Food - This type of black sludge is relatively common if you're cooking or eating, and fat or oil is involved. While it may happen with small amounts of oil, it's more common if you have a lot of oil in your sink. This is also more likely to happen if you have a garbage disposal that you are using.

Plumbing - If you have blocked plumbing, then you might be able to see black sludge in your drain from time to time. This can happen from a partial clog or a buildup of toilet paper. 

Mineral Deposits - If you have hard water, over time, mineral deposits are going to form in your drain. Some of these deposits are going to harden and turn into a black sludge that can be just as difficult to get rid of like hair. Although you can often get rid of the sludge by pouring boiling water into the drain, it may be better to call a plumber.

How to Deal With Black Sink Drain Discharge

You're probably wondering what you can do about black sludge in your sink or toilet. These are some things you can do:

  1. Clear the Drain - It sounds obvious, but if there is a clog in your drain and you can get to it easily, try to clear the drain yourself. If you can't, you can try to use a drain cleaner to clear it. If the drain is very clogged, the blockage may need to be removed by a professional.
  1. Try a Plunger - Plungers are very effective in clearing clogs, and if you can't get to them, you can try plunging from the side of the drain or above, slowly working the plunger down into the drain. You can also try plunging from below, going into the drain all the way if you can.

  1. Try a Drain Snake - For drain clogs that won't clear with a plunger, you can use a drain snake. They look like plungers, but they have a wire attached to the end and have a larger capacity to clear the drain. You have to be careful with these though, and make sure you don't damage your pipes. You can buy drain snakes or rent them from most hardware stores. Check out our DrainShroom hereTubShroom Metal Drain Snake in the Drain Openers department at
    1. Call a Plumber - If nothing else works, you'll need to call a plumber. This is definitely the last resort, but it's sometimes necessary to make sure the clog isn't worse than it looks.


There's nothing fun about seeing black sludge in your sink or toilet drain, but it's something that you're going to have to deal with from time to time. However, if you make sure to clean your sink drain regularly and keep these problems at bay, you shouldn't experience a black sludge buildup often.

Are you looking to eliminate plumbing problems and clogged drains for good? Look no further than our complete 'Shroom drain protection line! We have award-winning solutions for every drain in your home.

Say Goodbye to Clogged Drains Forever

We here at the TubShroom Company have made it our mission to protect every drain in the world from clogs. We know how annoying it can be to see that dirty water start backing up. Hair is the #1 cause of clogged drains, so we set out to develop products that can catch every hair, every time. Learn more about our TubShroom family of products here.


When your bathtub, shower, sink, or toilet drain clogs, you either try a "snake" device to clear it out or--more typically--you pour harmful chemicals down the drain to try to dissolve the clog. When those attempts fail, the next step most people take is to call on a plumber who may charge upwards of $200 to clear the clog. TubShroom products can prevent clogs before they occur.

View all our top-selling, award-winning TubShroom products here. From the TubShroom to SinkShroom, and DrainShroom to ToiletShroom, there's something for everyone. Click here to product your drains for good.


More Articles from The Shroom Company

How to Unclog a Toilet Without a Plunger: 3 Easy Methods

Before it Sinks In: 5 Reasons Why a Bathroom Sink Clogs

How to Unclog a Drain With Standing Water

The Ultimate Bathroom Cleaning Checklist


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