I cleaned mine with a mixture of bleach and water that I poured in and let it stand in the hose for some time. Then I hooked the hose to the sink and ran lots of water through it -- lots of black gunk left the hose. Then I made a dechlor solution and poured that in and sloshed it back and forth and let it sit and sloshed some more. Then ran lots more water. Sparkly clean hose!