Hi, I soak seeds in 5% household bleach (1 part bleach and 19 parts water). If they are robust seeds (hard-coated or hard to germinate), or if they have given me fungus problems before, I use 10% household bleach. I stir several times and let the seeds stay in the solution for 10 minutes, stirring every minute or two. I use this to clean up bulb scales and cuttings too. One other approach for keeping seedlings fungus-free is Consan or Physan (I generally use Consan Triple Action 20). I use 1 ounce per gallon of water mist the seeds and soil surface to full wetness. These gentle fungicides are biodegradable and have no lasting effect, so I mist the soil surface 2 or 3 times a week while seeds are germinating if I have a bit of fungus problem or if I'm dealing with a seed type that has had fungus problems before. I find Consan to be safe with even the tiniest seedling. Consan is a quaternary amine-type fungicide/bacteriocide, and essentially the same thing is used as a surface disinfectant in hospitals (floors, bathrooms, etc.). I also use Consan to wash down surfaces that have mildew and algae growing on them such as windows that get a lot of moisture, or lawn furniture, etc. Although a fungicide its toxicity is quite low compared to something like laundry detergent or even caffeine. I do take care not to get it in eyes or stay on skin, it can irritate. LINK: Consan FAQ (manufacturer's page) <A HREF="http://www.consan.net/faq.html">http://www.consan.net/faq.html</A> Cordially,