Ah the joys of having an outdoor/shed brewery.
I've had to start rinsing out my valentine arm before use as the slugs, snails and spiders like to crawl inside that... yuk!
The blue potable water hoses I use for both filling my hlt and chilling have the 'aquastop' fittings on the end that block the hose when it's not attached to something. I also drain them out as best I can before storing. I've never had any crud come out of them (or maybe they just prefer the valentine arm).