Robert Hooper , Mar 26, 2010; 12:10 a.m.
There are many different kinds of fungus that grow in lenses, and I have seen a lot of manifestations over the years. This definitely looks like fungus to me. I suspect just cleaning the element will leave spots where the fungal growth by-products have etched the coating and glass. A shame.
A 5w bulb is not nearly enough to prevent fungus from growing. You must add a higher wattage bulb to increase the internal temperature of the storage container to 10 degrees Fahrenheit above outside ambient Fahrenheit temperature in order for the method to be effective