# How to Clean a Dehumidifier Water Tank _Last updated: 2026-09-26_ ## Short answer Empty the tank, wash it with warm water and a little mild soap, rinse well, and let it dry completely before refitting. Do this every one to four weeks depending on use, and always dry the tank so mold and slime do not form between cycles. ## Why it matters - Standing condensate grows mold, slime and odors that the unit then blows into the room. - A sticky float or sensor can make the unit think the tank is full and stop collecting. - A dirty tank can also clog the drain path and cause leaks. ## Steps 1. Unplug the dehumidifier. 2. Remove the tank and empty it. 3. Wash the tank with warm water and a few drops of mild dish soap; a soft brush helps with slime. 4. Rinse thoroughly so no soap residue remains. 5. Wipe dry, then let it air-dry fully before refitting. 6. Check that the float moves freely and the tank seats correctly. 7. Clean or rinse the air filter while the tank is out. 8. Wipe any moisture around the tank bay and the drain opening. ## Prevent mold and slime - Do not leave water sitting in the tank when the unit is off. - Use continuous drainage for long runs so the tank stays dry. - Clean more often in warm, humid conditions. - Avoid harsh chemicals unless the manual allows them; they can damage plastic and seals. ## Common mistakes - Refitting a wet tank, which starts mold immediately. - Using bleach or abrasive cleaners that damage the plastic. - Ignoring the float, then wondering why the unit stops collecting. - Forgetting the air filter, which loads the coils. ## Sources Manufacturer cleaning instructions for your dehumidifier; general indoor-air guidance on preventing mold growth from standing water. ## Frequently asked questions **Q: How often should I clean the tank?** A: Every one to four weeks depending on how often the unit runs and how humid the space is. If you see slime or smell mustiness, clean it more often. **Q: Can I put the tank in the dishwasher?** A: Only if the manual says the tank is dishwasher safe. Heat can warp plastic and damage the float, so hand washing is the safer default. **Q: Should I use bleach?** A: Only if the manufacturer approves it. Mild soap and warm water are enough for routine cleaning, and harsh chemicals can damage seals and plastic. ## Recommended options Models with a continuous-drain outlet plus an easy-access tank are simpler to keep clean over time. - [DREO 4500 Sq Ft Smart Dehumidifier](https://www.amazon.com/dp/B0HFJ84RXX?maas=maas_adg_api_585602613512925350_static_12_201&ref_=aa_maas&tag=maas&aa_campaignid=PBd80bd4ce4ece40f44bcc76fcc0c48425&aa_adgroupid=d727cvIagGJNdGXDUz0Iqptw7I5s_aKKkTwS73Xa_a_b7ETmu9M7Nt_a8HDUDltLqXHEoBPCPgPBICz6Ie8_aV7Dy&aa_creativeid=3a3f9E4uc79Tu869imL_bB9Ebro5FEwJkM_aTxcggToEdOXnw_c) — DREO, rating 4.3/5 (244 reviews) - [DREO Energy Star Smart Dehumidifier](https://www.amazon.com/dp/B0GXY4C7NL?maas=maas_adg_api_585602613512925350_static_12_201&ref_=aa_maas&tag=maas&aa_campaignid=PBd80bd4ce4ece40f44bcc76fcc0c48425&aa_adgroupid=4df6yIkxpU3HN0REPqSNVtr6seTnE_aWp4t3Cqix8FL7SFdlrNERs9WYf2RDnowHAbQ7k5GcZAmD0uiaC3wUr&aa_creativeid=28f2gCwkqMXEzilBT4juHu3jBs9kdOytbk8aQjUCLZU4oS0_c) — DREO, rating 4.3/5 (244 reviews) _Some links on this page are affiliate links. We may earn a commission at no additional cost to you._ --- Canonical: