Cleaning Mold From a Keurig Coffee Maker's Water Reservoir

Updated on December 16, 2017

Coffee has become an essential part of modern life. I can hardly function without my morning brew. Keurig coffee makers are popular home coffee makers because they brew single cups of gourmet coffee in just a few seconds. But in order to keep the Keurig functioning properly and the coffee tasting great, it is important to clean the machine from time to time. Here are some tips to help you get the most from your Keurig.

Do I Really Need to Clean That Coffee Maker Resevoir?

The telltale signs that your coffee maker is overdue for cleaning:

  • mold (either visible scum or smell only)
  • slow drip
  • calcium buildup on parts

Did you know that routine cleanings will help ensure great-tasting coffee, coffee maker performance, and a germ-free machine? An uncleaned coffee maker can harbor mold and other harmful germs. The National Sanitation Foundation study found that kitchens were the “germiest” places in the home. The study went on to note that kitchen items, including coffee maker reservoirs, have higher germ counts than a bathroom doorknob or light switch.

White Vinegar: The Best Way to Clean a Dirty or Moldy Coffee Maker

That bottle of white vinegar in your kitchen cabinet is the best product to clean a Keurig coffee maker resevoir.
That bottle of white vinegar in your kitchen cabinet is the best product to clean a Keurig coffee maker resevoir. | Source

How to Clean your Keurig

Keurigs and other coffee makers can get clogged with hard water buildup. This accumulation leads to poor performance. The best way to remove buildup is to flush it out with white vinegar. This process is called "descaling."

  1. Pour an equal mixture of white vinegar and water into the water reservoir of your Keurig or coffee maker. Let this sit for a few minutes, to clean the reservoir and water intake hole.
  2. Run this solution through the machine with no K-cup inserted. If your Keurig has never been cleaned or is badly clogged, you may need to repeat the process more than once.
  3. Once you have run the white vinegar solution through your machine, run plain water through three or four times to rinse all of the vinegar.
  4. NOTE: If your Keurig is not for single servings and has a large reservoir that is never empty, you will need to rinse the reservoir out or run many more plain water operations through your machine.

Keurig Mini

Daily Care of Your Keurig Coffee Maker

  • Always use a clean cup to fill your machine. Using a dirty cup can introduce bacteria and mold, which can affect the taste of your coffee and possibly impact your health.
  • If you use a Keurig Mini or other single-serving coffee machine, consider leaving the reservoir lid open when not in use. This will allow the water tank to dry. A wet tank that is not used for a few days will is an ideal environment for mold, which would end up in your coffee the next time you use your machine.
  • Remove and clean the platform tray for mugs from time to time. Excess water and coffee drain into this tray and can cause gunk to develop. If you use your Keurig often, this tray will likely contain standing liquid and mold. Use a damp cloth and some dish soap to wipe any water away.
  • Avoid excessive buildup by using bottled instead of tap water. Bottled water has fewer minerals than tap water and will cause little or no buildup in your machine. Bottled water can be expensive, however. An affordable alternative is to use a water filter, which will remove most of the mineral content.

See How Else You Can Use White Vinegar In Your Home

Thanks for Reading!

I hope you found this Hub useful. If you liked what you read, please rate this hub and/or leave a comment. What has worked for you? Which devices or parts are really tough to clean? Please share your tips and experiences in the comments section below.

Last Cleaning Poll

When is the last time you cleaned your coffee maker?

See results


    0 of 8192 characters used
    Post Comment

    • profile image

      Jack 2 months ago

      If you take the bottom off are the plastic corrugated tubes black? Could they have mold?

    • profile image

      Richard Hurts 3 months ago

      What about killing the mold and bacteria in the Keurig? What about flushing with ammonia, alcohol, H2O2 or other’s. Ixyclean?

    • profile image

      silentmessage13 5 months ago

      if you use bleach it will only make the pink mold(same as in your tub) grow quicker. this is why vinegar is best. however if you do not run it threw every week and leave water lid and kcup lid open to dry your just going to keep getting it. the only way to actually clean it out is to replace parts completely or take it apart and spring clean the water valves and reservoir.

    • profile image

      ceecee 9 months ago

      It looks like there is slimy mold in the bottom that I can not reach. I have done everything possible to clean and remove it but the slimy mold like substance remains. Now this is a worthless appliance taking up space in my kitchen.

    • profile image

      Ken 14 months ago

      My B60 Keurig has interior water tank / boiler. Removal of this

      boiler tank for inspection and cleaning would be really

      nice, but alas - Keurig placed it inside a nearly Impregnable

      fortress and built everything around it. When we "descale"

      following the recommended procedure with white vinegar

      or descaling solution, the solution of course fills this boiler

      and cycles through it as you repeat the cup filling operation.

      You were on the right track by turning the machine over

      and shaking it.

      Here is what I do (accomplish at your own risk):

      1. unplug Keurig

      2. remove exterior water tank, cup tray, etc.

      3. turn Keurig upside down and smack it sharply on the bottom

      SEVERAL times or until you break your wrist (or a nail~:)

      4. Fill external reservoir with 50 / 50 filtered water + white

      vinegar solution and run at least 4 (large) cup cycles.

      5. after the last cup cycle, let the Keurig sit for 30+ minutes

      to allow the vinegar / water solution to dissolve scale, calcium,

      mold, etc. buildup inside the boiler tank, internal water pump,

      solenoids, lines, etc.

      6. empty and rinse the external tank with filtered (fresh) water

      and fill it with filtered water.

      7. run at least 6 large cup cycles to thoroughly flush all the internal

      liquid bearing components (boiler tank, etc) - refill the external

      tank as necessary (with filtered / fresh) water.

      I have used the above procedure several times on two Keurig

      machines to successfully restore normal flow (proper cup levels).

      Call me one of those "`lesses" (careless, fearless, senseless), but

      as long as the water is being properly heated I don't worry much

      about bacteria. If I'm drinking bacteria, I rationalize that it is dead

      bacteria (or at least scalded) and that helps me sleep at nite -

      lest of course if I've had more Caffeine than I should have ~:)

    • profile image

      Gail Mont 14 months ago

      There is an inside water reservoir which we cannot get to. I have turned my machine up side down and shook it, I can hear water moving about. How do we clean that...there has to be mold and bacteria there. Thanks for any suggestions

    • profile image

      afry 19 months ago

      I have a single serve and cannot remove the water reservoir. I have run through over 6 cycles of vinegar (plus rinsing with water) and still have black specks. :( Any suggestions?

    • profile image

      Carson collins 20 months ago

      Just got my keurig at a pawn shop didn't know it had a internel water don't know how long that water has been in the machine I think I'm going to throw it away and eat the $30.00 I payed for it

    • profile image

      Dan 21 months ago

      My Keurig took forever to reload water... The issue was the screen filter at the bottom of the water tank... It took a long phillips head screwdriver to remove the screen.... soaked it in vinegar over night and took a soft hobby acid brush to it..... removed all the green slim and rinced it well... reinstalled it and it reloads the water quickly.... ran white vinegar thru it and good to go.... so if your Keurig takes forever to load water check the metal round screen for slime

    • profile image

      Ken 2 years ago

      The water tank is dishwasher safe so it's OK to run it through a cleaning cycle.

    • profile image

      Karin 2 years ago

      Remove the water tank use your kitchen sink sprayer hold the tank upside down and spray hot water with high pressure up into the tank. This removed all the mold in the filter and hard to reach places. Of course do this after cleaning with detergent.

    • profile image

      ph 3 years ago

      I was told that even vinegar would not get rid of slime & mold in tubing, etc., other parts of a keyring.

    • profile image

      Margie L 5 years ago

      What should you do if you are going to be gone for a few months. How would you drain the water or prepare it so there is no problem when you return?

    • profile image

      Mt 5 years ago


    • profile image

      PatN 6 years ago

      Thanks for the help - we found it very useful. We get mold in our water reservoir occassionally and find it difficult to wipe the bottom clean - The white vinegar and leaving the lid open will help lots!

    • Jackie Lynnley profile image

      Jackie Lynnley 6 years ago from The Beautiful South

      Sounds great, voted it up, great name (lol) welcome to hubs!