I mostly use brew chlor from the grain and grape these days. Its slightly concentrated white king. After letting everything soak in the solution for at least 1/2 and hour I rinse thourghly, then use. So far (touch wood) I haven't had an infection. I used to use sodium met, but have read that it is rather nasty stuff to inhale. ( still use it, as campden tablets in winemaking )
cheers
Moray