Your Keurig coffee maker probably has mold in it. Just because it's handling all your daily caffeine needs, that doesn't mean you can just let it languish and assume it's cleaning itself.

If you use reusable K-Cups in your Keurig, now's the time to clean them. Place them in a large bowl full of soapy water and let them sit for five to 10 minutes. Use a bottle brush or narrow sponge ...

Be sure to check the owner's manual of your practical model, as recommended cleaning cadence will vary. For example, official guidance from Keurig suggests ... a small bristle brush, like a ...